sqlite3.h revision 3fcd43a0f1ef02756029e12af3cb9ba9faa13364
17790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
27790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** 2001 September 15
37790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
47790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The author disclaims copyright to this source code.  In place of
57790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a legal notice, here is a blessing:
67790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
77790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**    May you do good and not evil.
87790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**    May you find forgiveness for yourself and forgive others.
97790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**    May you share freely, never taking more than you give.
107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*************************************************************************
127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This header file defines the interface that the SQLite library
137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** presents to client programs.  If a C-function, structure, datatype,
147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or constant definition does not appear in this file, then it is
157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** not a published API of SQLite, is subject to change without
167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** notice, and should not be referenced by programs that use SQLite.
177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Some of the definitions that are in this file are marked as
197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** "experimental".  Experimental interfaces are normally new
20a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** features recently added to SQLite.  We do not anticipate changes
21a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to experimental interfaces but reserve the right to make minor changes
22a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if experience from use "in the wild" suggest such changes are prudent.
237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The official C-language API documentation for SQLite is derived
257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** from comments in this file.  This file is the authoritative source
267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** on how SQLite interfaces are suppose to operate.
277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The name of this file under configuration management is "sqlite.h.in".
297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The makefile makes some minor changes to this file (such as inserting
307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the version number) and changes its name to "sqlite3.h" as
317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** part of the build process.
327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifndef _SQLITE3_H_
347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define _SQLITE3_H_
357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#include <stdarg.h>     /* Needed for the definition of va_list */
367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Make sure we can call this stuff from C++.
397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef __cplusplus
417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectextern "C" {
427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Provide the ability to override linkage features of the interface.
477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifndef SQLITE_EXTERN
497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# define SQLITE_EXTERN extern
507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
51a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#ifndef SQLITE_API
52a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori# define SQLITE_API
53a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#endif
543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#ifndef SQLITE_CDECL
553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich# define SQLITE_CDECL
563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#endif
573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#ifndef SQLITE_STDCALL
583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich# define SQLITE_STDCALL
593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#endif
60a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
62a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These no-op macros are used in front of interfaces to mark those
63a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces as either deprecated or experimental.  New applications
643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** should not use deprecated interfaces - they are supported for backwards
65a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compatibility only.  Application writers should be aware that
66a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** experimental interfaces are subject to change in point releases.
67a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
68a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These macros used to resolve to various kinds of compiler magic that
69a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** would generate warning messages when they were used.  But that
70a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compiler magic ended up generating such a flurry of bug reports
71a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that we have taken it all out and gone back to using simple
72a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** noop macros.
73a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
74a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_DEPRECATED
75a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_EXPERIMENTAL
76a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
77a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
78a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Ensure these symbols were not defined by some previous header file.
797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_VERSION
817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# undef SQLITE_VERSION
827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_VERSION_NUMBER
847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# undef SQLITE_VERSION_NUMBER
857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
88a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Compile-Time Library Version Numbers
89a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
90a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
91a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** evaluates to a string literal that is the SQLite version in the
92a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** format "X.Y.Z" where X is the major version number (always 3 for
93a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite3) and Y is the minor version number and Z is the release number.)^
94a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
95a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
96a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** numbers used in [SQLITE_VERSION].)^
97a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
98a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be larger than the release from which it is derived.  Either Y will
99a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be held constant and Z will be incremented or else Y will be incremented
100a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and Z will be reset to zero.
101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
102a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Since version 3.6.18, SQLite source code has been stored in the
103a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <a href="http://www.fossil-scm.org/">Fossil configuration management
104de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
105a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a string which identifies a particular check-in of SQLite
106a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** within its configuration management system.  ^The SQLITE_SOURCE_ID
107a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** string contains the date and time of the check-in (UTC) and an SHA1
108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** hash of the entire source tree.
109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
110a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_libversion()],
111a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_libversion_number()], [sqlite3_sourceid()],
112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite_version()] and [sqlite_source_id()].
1137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
1143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_VERSION        "3.8.9"
1153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_VERSION_NUMBER 3008009
1163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SOURCE_ID      "2015-04-08 12:16:33 8a8ffc862e96f57aa698f93de10dee28e69f6e09"
1177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
1187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
119a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Run-Time Library Version Numbers
12071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** KEYWORDS: sqlite3_version, sqlite3_sourceid
1217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
122a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These interfaces provide the same information as the [SQLITE_VERSION],
123a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
124a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** but are associated with the library instead of the header file.  ^(Cautious
125a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** programmers might include assert() statements in their application to
126a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** verify that values returned by these interfaces match the macros in
127a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the header, and thus insure that the application is
128a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compiled with matching library and header files.
1297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
130a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <blockquote><pre>
131a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
132a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
133a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
134a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </pre></blockquote>)^
135a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
136a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
137a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** macro.  ^The sqlite3_libversion() function returns a pointer to the
138a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the sqlite3_version[] string constant.  The sqlite3_libversion()
139a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function is provided for use in DLLs since DLL users usually do not have
140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** direct access to string constants within the DLL.  ^The
141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_libversion_number() function returns an integer equal to
14271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [SQLITE_VERSION_NUMBER].  ^The sqlite3_sourceid() function returns
14371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** a pointer to a string constant whose value is the same as the
14471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [SQLITE_SOURCE_ID] C preprocessor macro.
145a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
146a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite_version()] and [sqlite_source_id()].
1477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
148a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu NoriSQLITE_API SQLITE_EXTERN const char sqlite3_version[];
1493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_libversion(void);
1503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_sourceid(void);
1513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_libversion_number(void);
1527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
1537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
15471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Run-Time Library Compilation Options Diagnostics
15571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
15671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The sqlite3_compileoption_used() function returns 0 or 1
15771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** indicating whether the specified option was defined at
15871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** compile time.  ^The SQLITE_ prefix may be omitted from the
15971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** option name passed to sqlite3_compileoption_used().
16071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
161de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_compileoption_get() function allows iterating
16271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** over the list of options that were defined at compile time by
16371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** returning the N-th compile time option string.  ^If N is out of range,
16471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
16571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** prefix is omitted from any strings returned by
16671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** sqlite3_compileoption_get().
16771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
16871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^Support for the diagnostic functions sqlite3_compileoption_used()
169de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and sqlite3_compileoption_get() may be omitted by specifying the
17071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
17171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
17271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** See also: SQL functions [sqlite_compileoption_used()] and
17371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [sqlite_compileoption_get()] and the [compile_options pragma].
17471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
17571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
1763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_compileoption_used(const char *zOptName);
1773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_compileoption_get(int N);
17871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#endif
17971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
18071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
181a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Test To See If The Library Is Threadsafe
182a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
183a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_threadsafe() function returns zero if and only if
18490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** SQLite was compiled with mutexing code omitted due to the
185a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_THREADSAFE] compile-time option being set to 0.
1867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite can be compiled with or without mutexes.  When
188a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
189a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are enabled and SQLite is threadsafe.  When the
190a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_THREADSAFE] macro is 0,
1917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the mutexes are omitted.  Without the mutexes, it is not safe
192a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to use SQLite concurrently from more than one thread.
1937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
194a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Enabling mutexes incurs a measurable performance penalty.
1957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** So if speed is of utmost importance, it makes sense to disable
1967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the mutexes.  But for maximum safety, mutexes should be enabled.
197a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The default behavior is for mutexes to be enabled.
1987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
199a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This interface can be used by an application to make sure that the
2007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** version of SQLite that it is linking against was compiled with
201a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the desired setting of the [SQLITE_THREADSAFE] macro.
202a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
203a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This interface only reports on the compile-time mutex setting
204a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
205a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
206a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be fully or partially disabled using a call to [sqlite3_config()]
207a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
2083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
209a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_threadsafe() function shows only the compile-time setting of
210a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** thread safety, not any run-time changes to that setting made by
211a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
212a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is unchanged by calls to sqlite3_config().)^
213a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
214a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See the [threading mode] documentation for additional information.
2157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
2163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_threadsafe(void);
2177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
2187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
219a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Database Connection Handle
2207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: {database connection} {database connections}
2217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
222a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Each open SQLite database is represented by a pointer to an instance of
223a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
2247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
225a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
2268fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and [sqlite3_close_v2()] are its destructors.  There are many other
2278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** interfaces (such as
228a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
229a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_busy_timeout()] to name but three) that are methods on an
230a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3 object.
2317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
2327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3 sqlite3;
2337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
2347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
235a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: 64-Bit Integer Types
2367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: sqlite_int64 sqlite_uint64
2377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Because there is no cross-platform way to specify 64-bit integer types
2397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite includes typedefs for 64-bit signed and unsigned integers.
2407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
241a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite_int64 and sqlite_uint64 types are supported for backwards
243a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compatibility only.
2447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
245a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_int64 and sqlite_int64 types can store integer values
246a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
247a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_uint64 and sqlite_uint64 types can store integer values
248a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** between 0 and +18446744073709551615 inclusive.
2497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
2507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_INT64_TYPE
2517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef SQLITE_INT64_TYPE sqlite_int64;
2527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
2537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#elif defined(_MSC_VER) || defined(__BORLANDC__)
2547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef __int64 sqlite_int64;
2557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef unsigned __int64 sqlite_uint64;
2567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#else
2577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef long long int sqlite_int64;
2587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  typedef unsigned long long int sqlite_uint64;
2597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
2607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef sqlite_int64 sqlite3_int64;
2617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef sqlite_uint64 sqlite3_uint64;
2627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
2637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If compiling for a processor that lacks floating point support,
265a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** substitute integer for floating-point.
2667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
2677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_OMIT_FLOATING_POINT
2687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# define double sqlite3_int64
2697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
2707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
2717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
272a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Closing A Database Connection
273a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2748fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
2758fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** for the [sqlite3] object.
2769bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
2778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the [sqlite3] object is successfully destroyed and all associated
2788fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** resources are deallocated.
2798fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
2808fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If the database connection is associated with unfinalized prepared
2818fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** statements or unfinished sqlite3_backup objects then sqlite3_close()
2828fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** will leave the database connection open and return [SQLITE_BUSY].
2838fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If sqlite3_close_v2() is called with unfinalized prepared statements
2849bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** and/or unfinished sqlite3_backups, then the database connection becomes
2858fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** an unusable "zombie" which will automatically be deallocated when the
2868fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** last prepared statement is finalized or the last sqlite3_backup is
2878fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** finished.  The sqlite3_close_v2() interface is intended for use with
2888fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** host languages that are garbage collected, and where the order in which
2898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** destructors are called is arbitrary.
2908fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
2918fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Applications should [sqlite3_finalize | finalize] all [prepared statements],
2928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_blob_close | close] all [BLOB handles], and
2938fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
2948fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** with the [sqlite3] object prior to attempting to close the object.  ^If
2958fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_close_v2() is called on a [database connection] that still has
2968fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** outstanding [prepared statements], [BLOB handles], and/or
2979bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
2988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** of resources is deferred until all [prepared statements], [BLOB handles],
2998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and [sqlite3_backup] objects are also destroyed.
3008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
3018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If an [sqlite3] object is destroyed while a transaction is open,
302a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the transaction is automatically rolled back.
303a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
3058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** must be either a NULL
306a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pointer or an [sqlite3] object pointer obtained
307a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from [sqlite3_open()], [sqlite3_open16()], or
308a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_open_v2()], and not previously closed.
3098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
3108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** argument is a harmless no-op.
3117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
3123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_close(sqlite3*);
3133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_close_v2(sqlite3*);
3147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
3157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The type for a callback function.
3177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This is legacy and deprecated.  It is included for historical
3187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** compatibility and is not documented.
3197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
3207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef int (*sqlite3_callback)(void*,int,char**, char**);
3217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
3227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
323a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: One-Step Query Execution Interface
324a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
325a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_exec() interface is a convenience wrapper around
326a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
327a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that allows an application to run multiple statements of SQL
328a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** without having to use a lot of C code.
329a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
331a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** semicolon-separate SQL statements passed into its 2nd argument,
332a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the context of the [database connection] passed in as its 1st
333a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** argument.  ^If the callback function of the 3rd argument to
334a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_exec() is not NULL, then it is invoked for each result row
335a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** coming out of the evaluated SQL statements.  ^The 4th argument to
33690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_exec() is relayed through to the 1st argument of each
337a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** callback invocation.  ^If the callback pointer to sqlite3_exec()
338a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is NULL, then no callback is ever invoked and result rows are
339a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ignored.
340a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
341a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an error occurs while evaluating the SQL statements passed into
342a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_exec(), then execution of the current statement stops and
343a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
344a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not NULL then any error message is written into memory obtained
345a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from [sqlite3_malloc()] and passed back through the 5th parameter.
346a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** To avoid memory leaks, the application should invoke [sqlite3_free()]
347a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on error message strings returned through the 5th parameter of
348a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of sqlite3_exec() after the error message string is no longer needed.
349a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
350a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
351a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** NULL before returning.
352a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
353a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
354a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine returns SQLITE_ABORT without invoking the callback again and
355a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** without running any subsequent SQL statements.
356a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
357a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The 2nd argument to the sqlite3_exec() callback function is the
358a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
359a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** callback is an array of pointers to strings obtained as if from
360a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_column_text()], one for each column.  ^If an element of a
361a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** result row is NULL then the corresponding string pointer for the
362a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
363a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_exec() callback is an array of pointers to strings where each
364a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** entry represents the name of corresponding result column as obtained
365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from [sqlite3_column_name()].
366a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
367a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
368a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to an empty string, or a pointer that contains only whitespace and/or
369a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL comments, then no SQL statements are evaluated and the database
370a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not changed.
371a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
372a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Restrictions:
3737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
374a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <ul>
375a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> The application must insure that the 1st parameter to sqlite3_exec()
376a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      is a valid and open [database connection].
3778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li> The application must not close the [database connection] specified by
378a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
379a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> The application must not modify the SQL statement text passed into
380a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
381a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </ul>
3827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
3833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_exec(
3847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,                                  /* An open database */
385a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const char *sql,                           /* SQL to be evaluated */
3867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*callback)(void*,int,char**,char**),  /* Callback function */
3877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *,                                    /* 1st argument to callback */
3887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char **errmsg                              /* Error msg written here */
3897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
3907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
3917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
392a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Result Codes
3939bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** KEYWORDS: {result code definitions}
3947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Many SQLite functions return an integer result code from the set shown
39690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** here in order to indicate success or failure.
3977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
398a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New error codes may be added in future versions of SQLite.
399a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4009bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** See also: [extended result code definitions]
4017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
4027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_OK           0   /* Successful result */
4037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/* beginning-of-error-codes */
4047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ERROR        1   /* SQL error or missing database */
4057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
4067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_PERM         3   /* Access permission denied */
4077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ABORT        4   /* Callback routine requested an abort */
4087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_BUSY         5   /* The database file is locked */
4097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCKED       6   /* A table in the database is locked */
4107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_NOMEM        7   /* A malloc() failed */
4117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
4127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
4137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
4147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
41590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
4167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_FULL        13   /* Insertion failed because database is full */
4177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
41871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
4197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_EMPTY       16   /* Database is empty */
4207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_SCHEMA      17   /* The database schema changed */
4217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
4227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
4237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MISMATCH    20   /* Data type mismatch */
4247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MISUSE      21   /* Library used incorrectly */
4257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
4267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_AUTH        23   /* Authorization denied */
4277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_FORMAT      24   /* Auxiliary database format error */
4287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
4297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_NOTADB      26   /* File opened that is not a database file */
4308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
4318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
4327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
4337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
4347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/* end-of-error-codes */
4357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
4367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
437a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Extended Result Codes
4389bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** KEYWORDS: {extended result code definitions}
4397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4409bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** In its default configuration, SQLite API routines return one of 30 integer
4419bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [result codes].  However, experience has shown that many of
442a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** these result codes are too coarse-grained.  They do not provide as
4437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** much information about problems as programmers might like.  In an effort to
4447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** address this, newer versions of SQLite (version 3.3.8 and later) include
4457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** support for additional result codes that provide more detailed information
4469bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** about errors. These [extended result codes] are enabled or disabled
447a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on a per database connection basis using the
4489bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [sqlite3_extended_result_codes()] API.  Or, the extended code for
4499bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** the most recent error can be obtained using
4509bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [sqlite3_extended_errcode()].
4517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
452a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
453a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
454a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
455a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
456a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
457a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
458a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
459a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
460a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
461a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
462a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
463a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
464a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
465a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
466a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
467a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
468a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
46971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
47071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
47171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
47290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
47390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
4748fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
4758fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
4768fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
4778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
47871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
47971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
4808fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
48171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
4828fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
4838fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
4848fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
48590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
48690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
48790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
4888fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
4898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
490c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
4918fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
4928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
4938fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
4948fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
4958fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
4968fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
4978fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
4988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
4998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
5008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
5018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
5028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
5038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
5043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
5057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
5067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
507a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Flags For File Open Operations
5087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These bit values are intended for use in the
5107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** 3rd parameter to the [sqlite3_open_v2()] interface and
51190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
5127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
513a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
514a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
515a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
516a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
517a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
51871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
51990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
5208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
521a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
522a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
523a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
524a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
525a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
526a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
527a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
528a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
529a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
530a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
531a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
532de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
5337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
53490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/* Reserved:                         0x00F00000 */
53590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
5367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
537a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Device Characteristics
5387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
539de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The xDeviceCharacteristics method of the [sqlite3_io_methods]
5408fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** object returns an integer which is a vector of these
5417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** bit values expressing I/O characteristics of the mass storage
5427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** device that holds the file that the [sqlite3_io_methods]
5437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** refers to.
5447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The SQLITE_IOCAP_ATOMIC property means that all writes of
5467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
5477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** mean that writes of blocks that are nnn bytes in size and
5487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are aligned to an address which is an integer multiple of
5497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
5507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** that when data is appended to a file, the data is appended
5517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** first then the size of the file is extended, never the other
5527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
5537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** information is written to disk in the same order as calls
55490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
55590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** after reboot following a crash or power loss, the only bytes in a
55690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** file that were written at the application level might have changed
55790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** and that adjacent bytes, even bytes within the same sector are
5588fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
5591c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** flag indicate that a file cannot be deleted when open.  The
5601c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
5611c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** read-only media and cannot be changed even by processes with
5621c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** elevated privileges.
5637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
564176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC                 0x00000001
565176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC512              0x00000002
566176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC1K               0x00000004
567176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC2K               0x00000008
568176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC4K               0x00000010
569176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC8K               0x00000020
570176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC16K              0x00000040
571176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC32K              0x00000080
572176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_ATOMIC64K              0x00000100
573176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
574176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
575176bf03af2edfb2a45b66dcb5daf822cc50c499eVasu Nori#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
57690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
5771c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define SQLITE_IOCAP_IMMUTABLE              0x00002000
5787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
5797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
580a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: File Locking Levels
5817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite uses one of these integer values as the second
5837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** argument to calls it makes to the xLock() and xUnlock() methods
5847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of an [sqlite3_io_methods] object.
5857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
5867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCK_NONE          0
5877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCK_SHARED        1
5887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCK_RESERVED      2
5897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCK_PENDING       3
5907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LOCK_EXCLUSIVE     4
5917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
5927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
593a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Synchronization Type Flags
5947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** When SQLite invokes the xSync() method of an
5967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_io_methods] object it uses a combination of
5977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** these integer values as the second argument.
5987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
6007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sync operation only needs to flush data to mass storage.  Inode
601a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** information need not be flushed. If the lower four bits of the flag
602a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
603a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If the lower four bits equal SQLITE_SYNC_FULL, that means
604a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to use Mac OS X style fullsync instead of fsync().
60595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
60695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
60795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
60895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** settings.  The [synchronous pragma] determines when calls to the
60995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** xSync VFS method occur and applies uniformly across all platforms.
61095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
61195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** energetic or rigorous or forceful the sync operations are and
61295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** only make a difference on Mac OSX for the default SQLite code.
61395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** (Third-party VFS implementations might also make the distinction
61495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
61595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** operating systems natively supported by SQLite, only Mac OSX
61695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** cares about the difference.)
6177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
6187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_SYNC_NORMAL        0x00002
6197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_SYNC_FULL          0x00003
6207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_SYNC_DATAONLY      0x00010
6217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
6227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
623a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: OS Interface Open File Handle
6247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
625a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** An [sqlite3_file] object represents an open file in the
626a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_vfs | OS interface layer].  Individual OS interface
627a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementations will
6287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** want to subclass this object by appending additional fields
6297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for their own use.  The pMethods entry is a pointer to an
6307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_io_methods] object that defines methods for performing
6317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** I/O operations on the open file.
6327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
6337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_file sqlite3_file;
6347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_file {
6357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
6367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
6377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
6387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
639a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: OS Interface File Virtual Methods Object
640a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
64190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Every file opened by the [sqlite3_vfs.xOpen] method populates an
642a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_file] object (or, more commonly, a subclass of the
643a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_file] object) with a pointer to an instance of this object.
644a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This object defines the methods used to perform various operations
645a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** against the open file represented by the [sqlite3_file] object.
6467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
64790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
648a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
64990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
65090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
65190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
65290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to NULL.
6537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
6557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
656a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
657a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** flag may be ORed in to indicate that only the data of the file
658a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and not its inode needs to be synced.
659a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The integer values to xLock() and xUnlock() are one of
6617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
6627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_LOCK_NONE],
6637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_LOCK_SHARED],
6647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_LOCK_RESERVED],
6657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_LOCK_PENDING], or
6667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_LOCK_EXCLUSIVE].
6677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </ul>
668a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xLock() increases the lock. xUnlock() decreases the lock.
669a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The xCheckReservedLock() method checks whether any database connection,
670a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** either in this process or in some other process, is holding a RESERVED,
6717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** PENDING, or EXCLUSIVE lock on the file.  It returns true
672a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if such a lock exists and false otherwise.
673a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The xFileControl() method is a generic interface that allows custom
6757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** VFS implementations to directly control an open file using the
676a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_file_control()] interface.  The second "op" argument is an
677a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** integer opcode.  The third argument is a generic pointer intended to
678a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** point to a structure that may contain arguments or space in which to
6797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** write return values.  Potential uses for xFileControl() might be
6807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** functions to enable blocking locks with timeouts, to change the
6817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** locking strategy (for example to use dot-file locks), to inquire
6827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** about the status of a lock, or to break stale locks.  The SQLite
683a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** core reserves all opcodes less than 100 for its own use.
6849bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** A [file control opcodes | list of opcodes] less than 100 is available.
685a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Applications that define a custom xFileControl method should use opcodes
68690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** greater than 100 to avoid conflicts.  VFS implementations should
68790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** return [SQLITE_NOTFOUND] for file control opcodes that they do not
68890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** recognize.
6897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The xSectorSize() method returns the sector size of the
6917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** device that underlies the file.  The sector size is the
6927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** minimum write that can be performed without disturbing
6937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** other bytes in the file.  The xDeviceCharacteristics()
6947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** method returns a bit vector describing behaviors of the
6957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** underlying device:
6967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
6987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC]
6997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC512]
7007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC1K]
7017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC2K]
7027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC4K]
7037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC8K]
7047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC16K]
7057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC32K]
7067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_ATOMIC64K]
7077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_SAFE_APPEND]
7087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_IOCAP_SEQUENTIAL]
7097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </ul>
7107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
7117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The SQLITE_IOCAP_ATOMIC property means that all writes of
7127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
7137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** mean that writes of blocks that are nnn bytes in size and
7147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are aligned to an address which is an integer multiple of
7157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
7167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** that when data is appended to a file, the data is appended
7177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** first then the size of the file is extended, never the other
7187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
7197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** information is written to disk in the same order as calls
7207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to xWrite().
721a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
722a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
723a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the unread portions of the buffer with zeros.  A VFS that
724a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** fails to zero-fill short reads might seem to work.  However,
725a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** failure to zero-fill short reads will eventually lead to
726a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database corruption.
7277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
7287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_io_methods sqlite3_io_methods;
7297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_io_methods {
7307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int iVersion;
7317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xClose)(sqlite3_file*);
7327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
7337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
7347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
7357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xSync)(sqlite3_file*, int flags);
7367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
7377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xLock)(sqlite3_file*, int);
7387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xUnlock)(sqlite3_file*, int);
739a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
7407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
7417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xSectorSize)(sqlite3_file*);
7427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xDeviceCharacteristics)(sqlite3_file*);
74371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  /* Methods above are valid for version 1 */
744de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
74571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
74671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  void (*xShmBarrier)(sqlite3_file*);
747de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
74871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  /* Methods above are valid for version 2 */
7498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
7508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
7518fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  /* Methods above are valid for version 3 */
7527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  /* Additional methods may be added in future releases */
7537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
7547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
7557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
756a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Standard File Control Opcodes
7579bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** KEYWORDS: {file control opcodes} {file control opcode}
7587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
7597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These integer constants are opcodes for the xFileControl method
760a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
7617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface.
7627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
7633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <ul>
7643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <li>[[SQLITE_FCNTL_LOCKSTATE]]
7657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
7667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** opcode causes the xFileControl method to write the current state of
7677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
7687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
7697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** into an integer that the pArg argument points to. This capability
7703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is used during testing and is only available when the SQLITE_TEST
7713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** compile-time option is used.
7723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
773c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_SIZE_HINT]]
77471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
77571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** layer a hint of how large the database file will grow to be during the
77671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** current transaction.  This hint is not guaranteed to be accurate but it
77771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** is often close.  The underlying VFS might choose to preallocate database
77871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** file space based on this hint in order to help writes to the database
77971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** file run faster.
780de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
781c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
782de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
783de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** extends and truncates the database file in chunks of a size specified
784de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** by the user. The fourth argument to [sqlite3_file_control()] should
785de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** point to an integer (type int) containing the new chunk-size to use
786de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** for the nominated database. Allocating database file space in large
787de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** chunks (say 1MB at a time), may reduce file-system fragmentation and
788de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** improve performance on some systems.
78990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
790c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_FILE_POINTER]]
79190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
79290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to the [sqlite3_file] object associated with a particular database
79390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** connection.  See the [sqlite3_file_control()] documentation for
79490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** additional information.
79590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
796c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
7978fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** No longer in use.
7988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
7998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_SYNC]]
8008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
8018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sent to the VFS immediately before the xSync method is invoked on a
8028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** database file descriptor. Or, if the xSync method is not invoked
8038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** because the user has configured SQLite with
8048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
8058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** of the xSync method. In most cases, the pointer argument passed with
8068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** this file-control is NULL. However, if the database file is being synced
8078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** as part of a multi-database commit, the argument points to a nul-terminated
8088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** string containing the transactions master-journal file name. VFSes that
8098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** do not need this signal should silently ignore this opcode. Applications
8108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** should not call [sqlite3_file_control()] with this opcode as doing so may
8118fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** disrupt the operation of the specialized VFSes that do require it.
8128fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
8138fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
8148fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
8158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and sent to the VFS after a transaction has been committed immediately
8168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** but before the database is unlocked. VFSes that do not need this signal
8178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** should silently ignore this opcode. Applications should not call
8188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_file_control()] with this opcode as doing so may disrupt the
8198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** operation of the specialized VFSes that do require it.
82090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
821c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
82290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
82390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** retry counts and intervals for certain disk I/O operations for the
82490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** windows [VFS] in order to provide robustness in the presence of
82590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** anti-virus programs.  By default, the windows VFS will retry file read,
82690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** file write, and file delete operations up to 10 times, with a delay
82790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of 25 milliseconds before the first retry and with the delay increasing
82890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** by an additional 25 milliseconds with each subsequent retry.  This
82990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** opcode allows these two values (10 retries and 25 milliseconds of delay)
83090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to be adjusted.  The values are changed for all database connections
83190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** within the same process.  The argument is a pointer to an array of two
83290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** integers where the first integer i the new retry count and the second
83390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** integer is the delay.  If either integer is negative, then the setting
83490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is not changed but instead the prior value of that setting is written
83590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** into the array entry, allowing the current retry settings to be
83690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** interrogated.  The zDbName parameter is ignored.
83790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
838c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
83990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
8408fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
84190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** write ahead log and shared memory files used for transaction control
84290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** are automatically deleted when the latest connection to the database
84390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** closes.  Setting persistent WAL mode causes those files to persist after
84490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** close.  Persisting the files is useful when other processes that do not
84590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** have write permission on the directory containing the database file want
84690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to read the database file, as the WAL and shared memory files must exist
84790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** in order for the database to be readable.  The fourth parameter to
84890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
84990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
85090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** WAL mode.  If the integer is -1, then it is overwritten with the current
85190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** WAL persistence setting.
85290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
853c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
85490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
85590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
85690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
85790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** xDeviceCharacteristics methods. The fourth parameter to
85890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
85990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
86090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** mode.  If the integer is -1, then it is overwritten with the current
86190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** zero-damage mode setting.
86290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
863c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_OVERWRITE]]
86490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
86590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a write transaction to indicate that, unless it is rolled back for some
86690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** reason, the entire database file will be overwritten by the current
86790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** transaction. This is used by VACUUM operations.
86890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
869c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_VFSNAME]]
87090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
87190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
87290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** final bottom-level VFS are written into memory obtained from
87390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_malloc()] and the result is stored in the char* variable
87490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** that the fourth parameter of [sqlite3_file_control()] points to.
87590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The caller is responsible for freeing the memory when done.  As with
87690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** all file-control actions, there is no guarantee that this will actually
87790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** do anything.  Callers should initialize the char* variable to a NULL
87890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** pointer in case this file-control is not implemented.  This file-control
87990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is intended for diagnostic use only.
880c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown**
881c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** <li>[[SQLITE_FCNTL_PRAGMA]]
882c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
883c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** file control is sent to the open [sqlite3_file] object corresponding
884c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** to the database file to which the pragma statement refers. ^The argument
885c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
886c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** pointers to strings (char**) in which the second element of the array
887c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** is the name of the pragma and the third element is the argument to the
888c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** pragma or NULL if the pragma has no argument.  ^The handler for an
889c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
890c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** of the char** argument point to a string obtained from [sqlite3_mprintf()]
891c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** or the equivalent and that string will become the result of the pragma or
892c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** the error message if the pragma fails. ^If the
893c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
894c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
895c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** file control returns [SQLITE_OK], then the parser assumes that the
896c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** VFS has handled the PRAGMA itself and the parser generates a no-op
8973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** prepared statement if result string is NULL, or that returns a copy
8983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of the result string if the string is non-NULL.
8993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
900c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
901c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** that the VFS encountered an error while handling the [PRAGMA] and the
902c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
903c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** file control occurs at the beginning of pragma statement analysis and so
904c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** it is able to override built-in [PRAGMA] statements.
9058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
9078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The [SQLITE_FCNTL_BUSYHANDLER]
9088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** file-control may be invoked by SQLite on the database file handle
9098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** shortly after it is opened in order to provide a custom VFS with access
9108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to the connections busy-handler callback. The argument is of type (void **)
9118fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** - an array of two (void *) values. The first (void *) actually points
9128fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to a function of type (int (*)(void *)). In order to invoke the connections
9138fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** busy-handler, this function should be invoked with the second (void *) in
9148fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the array as the only argument. If it returns non-zero, then the operation
9158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** should be retried. If it returns zero, the custom VFS should abandon the
9168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** current operation.
9178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
9198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
9208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to have SQLite generate a
9218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** temporary filename using the same algorithm that is followed to generate
9228fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** temporary filenames for TEMP tables and other internal uses.  The
9238fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** argument should be a char** which will be filled with the filename
9248fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** written into memory obtained from [sqlite3_malloc()].  The caller should
9258fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** invoke [sqlite3_free()] on the result to avoid a memory leak.
9268fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
9288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
9298fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** maximum number of bytes that will be used for memory-mapped I/O.
9308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The argument is a pointer to a value of type sqlite3_int64 that
9318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** is an advisory maximum number of bytes in the file to memory map.  The
9328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** pointer is overwritten with the old value.  The limit is not changed if
9338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the value originally pointed to is negative, and so the current limit
9348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** can be queried by passing in a pointer to a negative number.  This
9358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** file-control is used internally to implement [PRAGMA mmap_size].
9368fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9378fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_TRACE]]
9388fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_FCNTL_TRACE] file control provides advisory information
9398fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to the VFS about what the higher layers of the SQLite stack are doing.
9408fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** This file control is used by some VFS activity tracing [shims].
9418fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The argument is a zero-terminated string.  Higher layers in the
9428fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQLite stack may generate instances of this file control if
9438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
9448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li>[[SQLITE_FCNTL_HAS_MOVED]]
9468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
9478fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** pointer to an integer and it writes a boolean into that integer depending
9488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** on whether or not the file has been renamed, moved, or deleted since it
9498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** was first opened.
9508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
9511c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
9521c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
9531c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** opcode causes the xFileControl method to swap the file handle with the one
9541c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** pointed to by the pArg argument.  This capability is used during testing
9551c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** and only needs to be supported when SQLITE_TEST is defined.
9561c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
9573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
9583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
9593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** be advantageous to block on the next WAL lock if the lock is not immediately
9603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** available.  The WAL subsystem issues this signal during rare
9613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** circumstances in order to fix a problem with priority inversion.
9623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Applications should <em>not</em> use this file-control.
9633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
964c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** </ul>
96590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
96690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_LOCKSTATE               1
9673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
9683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
9693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_FCNTL_LAST_ERRNO              4
97090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_SIZE_HINT               5
97190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_CHUNK_SIZE              6
97290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_FILE_POINTER            7
97390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_SYNC_OMITTED            8
97490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_WIN32_AV_RETRY          9
97590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_PERSIST_WAL            10
97690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_OVERWRITE              11
97790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_VFSNAME                12
97890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
979c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown#define SQLITE_FCNTL_PRAGMA                 14
9808fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_BUSYHANDLER            15
9818fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_TEMPFILENAME           16
9828fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_MMAP_SIZE              18
9838fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_TRACE                  19
9848fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_HAS_MOVED              20
9858fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_SYNC                   21
9868fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_FCNTL_COMMIT_PHASETWO        22
9871c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
9883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_FCNTL_WAL_BLOCK              24
9893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich
9903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich/* deprecated names */
9913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
9923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
9933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
9943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich
9957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
9967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
997a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Mutex Handle
9987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
9997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The mutex module within SQLite defines [sqlite3_mutex] to be an
10007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** abstract type for a mutex object.  The SQLite core never looks
10017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** at the internal representation of an [sqlite3_mutex].  It only
10027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** deals with pointers to the [sqlite3_mutex] object.
10037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
10047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Mutexes are created using [sqlite3_mutex_alloc()].
10057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
10067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_mutex sqlite3_mutex;
10077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
10087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
1009a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: OS Interface Object
10107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1011a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** An instance of the sqlite3_vfs object defines the interface between
1012a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the SQLite core and the underlying operating system.  The "vfs"
101390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** in the name of the object stands for "virtual file system".  See
101490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the [VFS | VFS documentation] for further information.
10157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1016a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The value of the iVersion field is initially 1 but may be larger in
1017a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** future versions of SQLite.  Additional fields may be appended to this
1018a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** object when the iVersion value is increased.  Note that the structure
1019a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the sqlite3_vfs object changes in the transaction between
1020a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1021a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** modified.
10227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
10237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The szOsFile field is the size of the subclassed [sqlite3_file]
10247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** structure used by this VFS.  mxPathname is the maximum length of
10257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a pathname in this VFS.
10267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
10277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Registered sqlite3_vfs objects are kept on a linked list formed by
10287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the pNext pointer.  The [sqlite3_vfs_register()]
10297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and [sqlite3_vfs_unregister()] interfaces manage this list
10307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1031a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** searches the list.  Neither the application code nor the VFS
1032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation should use the pNext pointer.
10337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The pNext field is the only field in the sqlite3_vfs
10357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** structure that SQLite will ever modify.  SQLite will only access
10367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or modify this field while holding a particular static mutex.
10377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The application should never modify anything within the sqlite3_vfs
10387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** object once the object has been registered.
10397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
10407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The zName field holds the name of the VFS module.  The name must
10417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** be unique across all VFS modules.
10427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
104390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[sqlite3_vfs.xOpen]]
1044de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite guarantees that the zFilename parameter to xOpen
1045a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is either a NULL pointer or string obtained
1046de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** from xFullPathname() with an optional suffix added.
1047de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If a suffix is added to the zFilename parameter, it will
1048de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** consist of a single "-" character followed by no more than
104990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** 11 alphanumeric and/or "-" characters.
1050de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite further guarantees that
1051a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the string will be valid and unchanged until xClose() is
1052a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** called. Because of the previous sentence,
1053a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [sqlite3_file] can safely store a pointer to the
10547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** filename if it needs to remember the filename for some reason.
1055de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1056de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** must invent its own temporary name for the file.  ^Whenever the
1057a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xFilename parameter is NULL it will also be the case that the
1058a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
10597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1060a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The flags argument to xOpen() includes all bits set in
10617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
10627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or [sqlite3_open16()] is used, then flags includes at least
1063a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
10647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If xOpen() opens a file read-only then it sets *pOutFlags to
1065a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1066a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1067de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(SQLite will also add one of the following flags to the xOpen()
10687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** call, depending on the object being opened:
1069a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
10707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
10717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_MAIN_DB]
10727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
10737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_TEMP_DB]
10747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
10757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_TRANSIENT_DB]
10767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_SUBJOURNAL]
10777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
1078de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li>  [SQLITE_OPEN_WAL]
1079de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ul>)^
10807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
10817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The file I/O implementation can use the object type flags to
1082a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** change the way it deals with files.  For example, an application
10837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** that does not care about crash recovery or rollback might make
10847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the open of a journal file a no-op.  Writes to this journal would
1085a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** also be no-ops, and any attempt to read the journal would return
1086a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_IOERR.  Or the implementation might recognize that a database
1087a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** file will be doing page-aligned sector reads and writes in a random
10887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** order and set up its I/O subsystem accordingly.
1089a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1090a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite might also add one of the following flags to the xOpen method:
1091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
10927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
10937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_OPEN_DELETEONCLOSE]
10947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> [SQLITE_OPEN_EXCLUSIVE]
10957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </ul>
1096a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1097a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1098de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1099de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** will be set for TEMP databases and their journals, transient
1100de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** databases, and subjournals.
1101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1102de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1103a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1104a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1105a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1106a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_OPEN_CREATE, is used to indicate that file should always
1107a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be created, and that it is an error if it already exists.
1108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** It is <i>not</i> used to indicate the file should be opened
1109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for exclusive access.
1110a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1111de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^At least szOsFile bytes of memory are allocated by SQLite
1112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to hold the  [sqlite3_file] structure passed as the third
1113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** argument to xOpen.  The xOpen method does not have to
1114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocate the structure; it should just fill it in.  Note that
1115a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the xOpen method must set the sqlite3_file.pMethods to either
1116a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1117a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1118a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** element will be valid after xOpen returns regardless of the success
1119a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or failure of the xOpen call.
1120a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
112190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[sqlite3_vfs.xAccess]]
1122de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1123a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1124a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1125a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to test whether a file is at least readable.   The file can be a
11267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** directory.
1127a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1128de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite will always allocate at least mxPathname+1 bytes for the
1129a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** output buffer xFullPathname.  The exact size of the output buffer
1130a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is also passed as a parameter to both  methods. If the output buffer
1131a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1132a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** handled as a fatal error by SQLite, vfs implementations should endeavor
1133a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to prevent this by setting mxPathname to a sufficiently large value.
1134a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1135ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1136ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** interfaces are not strictly a part of the filesystem, but they are
11377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** included in the VFS structure for completeness.
11387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The xRandomness() function attempts to return nBytes bytes
11397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of good-quality randomness into zOut.  The return value is
1140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the actual number of bytes of randomness obtained.
1141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The xSleep() method causes the calling thread to sleep for at
1142de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** least the number of microseconds given.  ^The xCurrentTime()
1143ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** method returns a Julian Day Number for the current date and time as
1144ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** a floating point value.
1145de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
114690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Day Number multiplied by 86400000 (the number of milliseconds in
1147ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** a 24-hour day).
1148ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** ^SQLite will use the xCurrentTimeInt64() method to get the current
1149ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** date and time if that method is available (if iVersion is 2 or
1150ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** greater and the function pointer is not NULL) and will fall back
1151ebc6b24ff37b903195b37f143a5791c9f02be8dfVasu Nori** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
115290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
115390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
115490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** are not used by the SQLite core.  These optional interfaces are provided
115590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** by some VFSes to facilitate testing of the VFS code. By overriding
115690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** system calls with functions under its control, a test program can
115790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** simulate faults and error conditions that would otherwise be difficult
115890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or impossible to induce.  The set of system calls that can be overridden
115990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** varies from one VFS to another, and from one version of the same VFS to the
116090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** next.  Applications that use these interfaces must be prepared for any
116190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or all of these interfaces to be NULL or for their behavior to change
116290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** from one release to the next.  Applications must not attempt to access
116390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** any of these methods if the iVersion of the VFS is less than 3.
11647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
11657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_vfs sqlite3_vfs;
116690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Browntypedef void (*sqlite3_syscall_ptr)(void);
11677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_vfs {
116890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int iVersion;            /* Structure version number (currently 3) */
11697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int szOsFile;            /* Size of subclassed sqlite3_file */
11707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int mxPathname;          /* Maximum file pathname length */
11717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_vfs *pNext;      /* Next registered VFS */
11727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zName;       /* Name of this virtual file system */
11737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *pAppData;          /* Pointer to application-specific data */
11747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
11757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project               int flags, int *pOutFlags);
11767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1177a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
11787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
11797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
11807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1181a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
11827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xDlClose)(sqlite3_vfs*, void*);
11837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
11847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xSleep)(sqlite3_vfs*, int microseconds);
11857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xCurrentTime)(sqlite3_vfs*, double*);
1186a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xGetLastError)(sqlite3_vfs*, int, char *);
118771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  /*
118871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  ** The methods above are in version 1 of the sqlite_vfs object
118971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  ** definition.  Those that follow are added in version 2 or later
119071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  */
119171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
119271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  /*
119371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
119490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  ** Those below are for version 3 and greater.
119590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  */
119690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
119790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
119890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
119990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  /*
120090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
120171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  ** New fields may be appended in figure versions.  The iVersion
120271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  ** value will increment whenever this happens.
120371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  */
12047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
12057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
12067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
1207a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Flags for the xAccess VFS method
1208a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1209a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These integer constants can be used as the third parameter to
1210a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the xAccess method of an [sqlite3_vfs] object.  They determine
1211a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** what kind of permissions the xAccess method is looking for.
1212a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** With SQLITE_ACCESS_EXISTS, the xAccess method
1213a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** simply checks whether the file exists.
1214a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** With SQLITE_ACCESS_READWRITE, the xAccess method
1215de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** checks whether the named directory is both readable and writable
1216de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** (in other words, if files can be added, removed, and renamed within
1217de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the directory).
1218de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1219de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [temp_store_directory pragma], though this could change in a future
1220de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** release of SQLite.
1221a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** With SQLITE_ACCESS_READ, the xAccess method
1222de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1223de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** currently unused, though it might be used in a future release of
1224de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** SQLite.
12257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
12267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ACCESS_EXISTS    0
1227de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1228de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#define SQLITE_ACCESS_READ      2   /* Unused */
12297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
12307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
123171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Flags for the xShmLock VFS method
123271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
123371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** These integer constants define the various locking operations
123471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** allowed by the xShmLock method of [sqlite3_io_methods].  The
123571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** following are the only legal combinations of flags to the
123671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** xShmLock method:
123771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
123871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <ul>
123971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
124071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
124171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
124271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
124371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** </ul>
124471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
124571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
12463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** was given on the corresponding lock.
124771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
124871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The xShmLock method can transition between unlocked and SHARED or
124971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
125071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** and EXCLUSIVE.
125171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
125271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_SHM_UNLOCK       1
125371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_SHM_LOCK         2
125471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_SHM_SHARED       4
125571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_SHM_EXCLUSIVE    8
125671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
125771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
125871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Maximum xShmLock index
125971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
126071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The xShmLock method on [sqlite3_io_methods] may use values
126171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** between 0 and this upper bound as its "offset" argument.
126271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The SQLite core will never attempt to acquire or release a
126371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** lock outside of this range
126471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
126571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_SHM_NLOCK        8
126671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
126771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
126871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
1269a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Initialize The SQLite Library
1270a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1271a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_initialize() routine initializes the
1272a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite library.  ^The sqlite3_shutdown() routine
1273a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** deallocates any resources that were allocated by sqlite3_initialize().
1274a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These routines are designed to aid in process initialization and
1275a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** shutdown on embedded systems.  Workstation applications using
1276a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite normally do not need to invoke either of these routines.
1277a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1278a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A call to sqlite3_initialize() is an "effective" call if it is
1279a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the first time sqlite3_initialize() is invoked during the lifetime of
1280a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the process, or if it is the first time sqlite3_initialize() is invoked
1281a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** following a call to sqlite3_shutdown().  ^(Only an effective call
1282a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of sqlite3_initialize() does any initialization.  All other calls
1283a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are harmless no-ops.)^
1284a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1285a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A call to sqlite3_shutdown() is an "effective" call if it is the first
1286a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1287a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an effective call to sqlite3_shutdown() does any deinitialization.
1288a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1289a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1290a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1291a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not.  The sqlite3_shutdown() interface must only be called from a
1292a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** single thread.  All open [database connections] must be closed and all
1293a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** other SQLite resources must be deallocated prior to invoking
1294a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_shutdown().
1295a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1296a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Among other things, ^sqlite3_initialize() will invoke
1297a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1298a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will invoke sqlite3_os_end().
1299a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1300a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1301a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If for some reason, sqlite3_initialize() is unable to initialize
1302a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the library (perhaps it is unable to allocate a needed resource such
1303a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** as a mutex) it returns an [error code] other than [SQLITE_OK].
1304a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1305a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_initialize() routine is called internally by many other
1306a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite interfaces so that an application usually does not need to
1307a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1308a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** calls sqlite3_initialize() so the SQLite library will be automatically
1309a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** initialized when [sqlite3_open()] is called if it has not be initialized
1310a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1311a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compile-time option, then the automatic calls to sqlite3_initialize()
1312a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are omitted and the application must call sqlite3_initialize() directly
1313a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prior to using any other SQLite interface.  For maximum portability,
1314a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is recommended that applications always invoke sqlite3_initialize()
1315a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** directly prior to using any other SQLite interface.  Future releases
1316a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of SQLite may require this.  In other words, the behavior exhibited
1317a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1318a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** default behavior in some future release of SQLite.
1319a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1320a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_os_init() routine does operating-system specific
1321a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** initialization of the SQLite library.  The sqlite3_os_end()
1322a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine undoes the effect of sqlite3_os_init().  Typical tasks
1323a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** performed by these routines include allocation or deallocation
1324a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of static resources, initialization of global variables,
1325a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** setting up a default [sqlite3_vfs] module, or setting up
1326a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a default configuration using [sqlite3_config()].
1327a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1328a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The application should never invoke either sqlite3_os_init()
1329a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or sqlite3_os_end() directly.  The application should only invoke
1330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1331a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface is called automatically by sqlite3_initialize() and
1332a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1333a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementations for sqlite3_os_init() and sqlite3_os_end()
1334a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1335a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When [custom builds | built for other platforms]
1336a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (using the [SQLITE_OS_OTHER=1] compile-time
1337a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** option) the application must supply a suitable implementation for
1338a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1339a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation of sqlite3_os_init() or sqlite3_os_end()
1340a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must return [SQLITE_OK] on success and some other [error code] upon
1341a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** failure.
1342a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
13433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_initialize(void);
13443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_shutdown(void);
13453fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_os_init(void);
13463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_os_end(void);
1347a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1348a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1349a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Configuring The SQLite Library
1350a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1351a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_config() interface is used to make global configuration
1352a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** changes to SQLite in order to tune SQLite to the specific needs of
1353a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the application.  The default configuration is recommended for most
1354a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** applications and so this routine is usually not necessary.  It is
1355a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** provided to support rare applications with unusual needs.
1356a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1357a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_config() interface is not threadsafe.  The application
1358a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must insure that no other SQLite interfaces are invoked by other
1359a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
1360a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** may only be invoked prior to library initialization using
1361a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1362a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1363a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1364a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Note, however, that ^sqlite3_config() can be called as part of the
1365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation of an application-defined [sqlite3_os_init()].
1366a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1367a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The first argument to sqlite3_config() is an integer
136890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [configuration option] that determines
1369a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** what property of SQLite is to be configured.  Subsequent arguments
137090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** vary depending on the [configuration option]
1371a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the first argument.
1372a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1373a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1374a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the option is unknown or SQLite is unable to set the option
1375a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then this routine returns a non-zero [error code].
1376a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
13773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_CDECL sqlite3_config(int, ...);
1378a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1379a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1380a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Configure database connections
1381a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1382a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_db_config() interface is used to make configuration
1383a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** changes to a [database connection].  The interface is similar to
1384a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] except that the changes apply to a single
138590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [database connection] (specified in the first argument).
1386a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1387a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The second argument to sqlite3_db_config(D,V,...)  is the
138890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
138990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** that indicates what aspect of the [database connection] is being configured.
139090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Subsequent arguments vary depending on the configuration verb.
1391a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1392a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1393a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the call is considered successful.
1394a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
13953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_CDECL sqlite3_db_config(sqlite3*, int op, ...);
1396a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1397a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1398a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Memory Allocation Routines
1399a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1400a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** An instance of this object defines the interface between SQLite
1401a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and low-level memory allocation routines.
1402a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1403a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This object is used in only one place in the SQLite interface.
1404a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A pointer to an instance of this object is the argument to
1405a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] when the configuration option is
1406a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1407a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** By creating an instance of this object
1408a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1409a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** during configuration, an application can specify an alternative
1410a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory allocation subsystem for SQLite to use for all of its
1411a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** dynamic memory needs.
1412a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1413a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Note that SQLite comes with several [built-in memory allocators]
1414a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that are perfectly adequate for the overwhelming majority of applications
1415a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and that this object is only useful to a tiny minority of applications
1416a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with specialized memory allocation requirements.  This object is
1417a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** also used during testing of SQLite in order to specify an alternative
1418a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory allocator that simulates memory out-of-memory conditions in
1419a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** order to verify that SQLite recovers gracefully from such
1420a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** conditions.
1421a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
142290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The xMalloc, xRealloc, and xFree methods must work like the
142390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** malloc(), realloc() and free() functions from the standard C library.
142490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^SQLite guarantees that the second argument to
1425a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xRealloc is always a value returned by a prior call to xRoundup.
1426a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1427a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xSize should return the allocated size of a memory allocation
1428a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** previously obtained from xMalloc or xRealloc.  The allocated size
1429a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is always at least as big as the requested size but may be larger.
1430a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1431a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The xRoundup method returns what would be the allocated size of
1432a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a memory allocation given a particular requested size.  Most memory
1433a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocators round up memory allocations at least to the next multiple
1434a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1435a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Every memory allocation request coming in through [sqlite3_malloc()]
1436a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1437a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that causes the corresponding memory allocation to fail.
1438a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
14398fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The xInit method initializes the memory allocator.  For example,
1440a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it might allocate any require mutexes or initialize internal data
1441a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** structures.  The xShutdown method is invoked (indirectly) by
1442a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_shutdown()] and should deallocate any resources acquired
1443a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by xInit.  The pAppData pointer is used as the only parameter to
1444a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xInit and xShutdown.
1445a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1446a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1447a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the xInit method, so the xInit method need not be threadsafe.  The
1448a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xShutdown method is only called from [sqlite3_shutdown()] so it does
1449a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not need to be threadsafe either.  For all other methods, SQLite
1450a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1451a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1452a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is by default) and so the methods are automatically serialized.
1453a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1454a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** methods must be threadsafe or else make their own arrangements for
1455a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** serialization.
1456a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1457a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite will never invoke xInit() more than once without an intervening
1458a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call to xShutdown().
1459a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
1460a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noritypedef struct sqlite3_mem_methods sqlite3_mem_methods;
1461a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noristruct sqlite3_mem_methods {
1462a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *(*xMalloc)(int);         /* Memory allocation function */
1463a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xFree)(void*);          /* Free a prior allocation */
1464a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1465a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xSize)(void*);           /* Return the size of an allocation */
1466a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xRoundup)(int);          /* Round up request size to allocation size */
1467a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xInit)(void*);           /* Initialize the memory allocator */
1468a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1469a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *pAppData;                /* Argument to xInit() and xShutdown() */
1470a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori};
1471a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1472a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1473a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Configuration Options
147490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** KEYWORDS: {configuration option}
1475a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1476a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These constants are the available integer configuration options that
1477a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be passed as the first argument to the [sqlite3_config()] interface.
1478a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1479a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New configuration options may be added in future releases of SQLite.
1480a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Existing configuration options might be discontinued.  Applications
1481a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** should check the return code from [sqlite3_config()] to make sure that
1482a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the call worked.  The [sqlite3_config()] interface will return a
1483a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** non-zero [error code] if a discontinued or unsupported configuration option
1484a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is invoked.
1485a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1486a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
148790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1488a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>There are no arguments to this option.  ^This option sets the
1489a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [threading mode] to Single-thread.  In other words, it disables
1490a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** all mutexing and puts SQLite into a mode where it can only be used
1491a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by a single thread.   ^If SQLite is compiled with
1492a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1493a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is not possible to change the [threading mode] from its default
1494a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value of Single-thread and so [sqlite3_config()] will return
1495a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1496a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** configuration option.</dd>
1497a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
149890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1499a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>There are no arguments to this option.  ^This option sets the
1500a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [threading mode] to Multi-thread.  In other words, it disables
1501a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** mutexing on [database connection] and [prepared statement] objects.
1502a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The application is responsible for serializing access to
1503a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connections] and [prepared statements].  But other mutexes
1504a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are enabled so that SQLite will be safe to use in a multi-threaded
1505a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** environment as long as no two threads attempt to use the same
1506a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection] at the same time.  ^If SQLite is compiled with
1507a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1508a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is not possible to set the Multi-thread [threading mode] and
1509a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1510a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1511a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
151290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1513a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>There are no arguments to this option.  ^This option sets the
1514a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [threading mode] to Serialized. In other words, this option enables
1515a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** all mutexes including the recursive
1516a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** mutexes on [database connection] and [prepared statement] objects.
1517a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** In this mode (which is the default when SQLite is compiled with
1518a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1519a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to [database connections] and [prepared statements] so that the
1520a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** application is free to use the same [database connection] or the
1521a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** same [prepared statement] in different threads at the same time.
1522a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If SQLite is compiled with
1523a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1524a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is not possible to set the Serialized [threading mode] and
1525a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1526a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1527a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
152890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
15293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
15303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** a pointer to an instance of the [sqlite3_mem_methods] structure.
15313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The argument specifies
1532a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** alternative low-level memory allocation routines to be used in place of
1533a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the memory allocation routines built into SQLite.)^ ^SQLite makes
1534a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** its own private copy of the content of the [sqlite3_mem_methods] structure
1535a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** before the [sqlite3_config()] call returns.</dd>
1536a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
153790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
15383fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
15393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a pointer to an instance of the [sqlite3_mem_methods] structure.
15403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The [sqlite3_mem_methods]
1541a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** structure is filled with the currently defined memory allocation routines.)^
1542a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This option can be used to overload the default memory allocation
1543a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines with a wrapper that simulations memory allocation failure or
1544a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** tracks memory usage, for example. </dd>
1545a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
154690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
15473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
15483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** interpreted as a boolean, which enables or disables the collection of
15493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** memory allocation statistics. ^(When memory allocation statistics are
15503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** disabled, the following SQLite interfaces become non-operational:
1551a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <ul>
1552a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li> [sqlite3_memory_used()]
1553a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li> [sqlite3_memory_highwater()]
1554de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**   <li> [sqlite3_soft_heap_limit64()]
15553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> [sqlite3_status64()]
1556a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   </ul>)^
1557a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Memory allocation statistics are enabled by default unless SQLite is
1558a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1559a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocation statistics are disabled by default.
1560a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dd>
1561a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
156290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
15633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer
15643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** that SQLite can use for scratch memory.  ^(There are three arguments
15653fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to SQLITE_CONFIG_SCRATCH:  A pointer an 8-byte
156690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** aligned memory buffer from which the scratch allocations will be
1567a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** drawn, the size of each scratch allocation (sz),
15683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and the maximum number of scratch allocations (N).)^
1569a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The first argument must be a pointer to an 8-byte aligned buffer
1570a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of at least sz*N bytes of memory.
15713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^SQLite will not use more than one scratch buffers per thread.
15723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^SQLite will never request a scratch buffer that is more than 6
15733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** times the database page size.
15743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If SQLite needs needs additional
1575de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** scratch memory beyond what is provided by this configuration option, then
15763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_malloc()] will be used to obtain the memory needed.<p>
15773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^When the application provides any amount of scratch memory using
15783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large
15793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_malloc|heap allocations].
15803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This can help [Robson proof|prevent memory allocation failures] due to heap
15813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** fragmentation in low-memory embedded systems.
15823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </dd>
1583a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
158490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
15853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a static memory buffer
15863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** that SQLite can use for the database page cache with the default page
15873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** cache implementation.
1588a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This configuration should not be used if an application-define page
15893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]
15903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** configuration option.
15913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
15923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** 8-byte aligned
1593a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory, the size of each page buffer (sz), and the number of pages (N).
1594a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sz argument should be the size of the largest database page
15953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** (a power of two between 512 and 65536) plus some extra bytes for each
15963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** page header.  ^The number of extra bytes needed by the page header
15973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** can be determined using the [SQLITE_CONFIG_PCACHE_HDRSZ] option
15983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to [sqlite3_config()].
15993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^It is harmless, apart from the wasted memory,
16003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** for the sz parameter to be larger than necessary.  The first
16013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** argument should pointer to an 8-byte aligned block of memory that
16023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is at least sz*N bytes of memory, otherwise subsequent behavior is
16033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** undefined.
1604a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite will use the memory provided by the first argument to satisfy its
1605a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory needs for the first N pages that it adds to cache.  ^If additional
1606a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** page cache memory is needed beyond what is provided by this option, then
16073fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** SQLite goes to [sqlite3_malloc()] for the additional storage space.</dd>
1608a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
160990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
16103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
16113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** that SQLite will use for all of its dynamic memory allocation needs
16123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and
16133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_CONFIG_PAGECACHE].
16143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
16153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
16163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_ERROR] if invoked otherwise.
16173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^There are three arguments to SQLITE_CONFIG_HEAP:
16183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** An 8-byte aligned pointer to the memory,
1619a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the number of bytes in the memory buffer, and the minimum allocation size.
1620a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1621a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to using its default memory allocator (the system malloc() implementation),
1622a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
16233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** memory pointer is not NULL then the alternative memory
1624a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocator is engaged to handle all of SQLites memory allocation needs.
1625a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The first pointer (the memory pointer) must be aligned to an 8-byte
162690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** boundary or subsequent behavior of SQLite will be undefined.
162790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The minimum allocation size is capped at 2**12. Reasonable values
162890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** for the minimum allocation size are 2**5 through 2**8.</dd>
1629a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
163090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
16313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
16323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** pointer to an instance of the [sqlite3_mutex_methods] structure.
16333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The argument specifies alternative low-level mutex routines to be used
16343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
16353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the content of the [sqlite3_mutex_methods] structure before the call to
1636a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] returns. ^If SQLite is compiled with
1637a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1638a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the entire mutexing subsystem is omitted from the build and hence calls to
1639a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1640a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** return [SQLITE_ERROR].</dd>
1641a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
164290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
16433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
16443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1645a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_mutex_methods]
1646a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** structure is filled with the currently defined mutex routines.)^
1647a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This option can be used to overload the default mutex allocation
1648a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines with a wrapper used to track mutex usage for performance
1649a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** profiling or testing, for example.   ^If SQLite is compiled with
1650a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1651a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the entire mutexing subsystem is omitted from the build and hence calls to
1652a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1653a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** return [SQLITE_ERROR].</dd>
1654a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
165590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
16563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
16573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the default size of lookaside memory on each [database connection].
16583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The first argument is the
1659a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** size of each lookaside buffer slot and the second is the number of
16603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
16613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
16623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** option to [sqlite3_db_config()] can be used to change the lookaside
1663a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** configuration on individual connections.)^ </dd>
1664a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
166590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
16663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
16673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
16683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the interface to a custom page cache implementation.)^
16693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1670a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
167190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
16723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
16733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
16743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the current page cache implementation into that object.)^ </dd>
1675a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
167690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
16778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
16788fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** global [error log].
16798fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
168071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** function with a call signature of void(*)(void*,int,const char*),
168171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** and a pointer to void. ^If the function pointer is not NULL, it is
168271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** invoked by [sqlite3_log()] to process each logging event.  ^If the
168371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
168471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
168571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** passed through as the first parameter to the application-defined logger
168671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** function whenever that function is invoked.  ^The second parameter to
168771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** the logger function is a copy of the first parameter to the corresponding
168871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [sqlite3_log()] call and is intended to be a [result code] or an
168971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [extended result code].  ^The third parameter passed to the logger is
169071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** log message after formatting via [sqlite3_snprintf()].
169171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The SQLite logging interface is not reentrant; the logger function
169271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** supplied by the application must not invoke any SQLite interface.
169371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** In a multi-threaded application, the application-defined logger
169471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** function must be threadsafe. </dd>
169571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
169690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
16973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
16983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If non-zero, then URI handling is globally enabled. If the parameter is zero,
16993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** then URI handling is globally disabled.)^ ^If URI handling is globally
17003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
17013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_open16()] or
170290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** specified as part of [ATTACH] commands are interpreted as URIs, regardless
170390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
17048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** connection is opened. ^If it is globally disabled, filenames are
170590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
17068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** database connection is opened. ^(By default, URI handling is globally
170790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** disabled. The default value may be changed by compiling with the
17088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_USE_URI] symbol defined.)^
17098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
17108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
17113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
17123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** argument which is interpreted as a boolean in order to enable or disable
17133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the use of covering indices for full table scans in the query optimizer.
17143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The default setting is determined
17158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
17168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** if that compile-time option is omitted.
17178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The ability to disable the use of covering indices for full table scans
17188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** is because some incorrectly coded legacy applications might malfunction
17198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** when the optimization is enabled.  Providing the ability to
17208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** disable the optimization allows the older, buggy application code to work
17218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** without change even with newer versions of SQLite.
172290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
172390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
17248fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
172590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd> These options are obsolete and should not be used by new code.
172690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** They are retained for backwards compatibility but are now no-ops.
17278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** </dd>
17288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
17298fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_CONFIG_SQLLOG]]
17308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dt>SQLITE_CONFIG_SQLLOG
17318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd>This option is only available if sqlite is compiled with the
17328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
17338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
17348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The second should be of type (void*). The callback is invoked by the library
17358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** in three separate circumstances, identified by the value passed as the
17368fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** fourth parameter. If the fourth parameter is 0, then the database connection
17378fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** passed as the second argument has just been opened. The third argument
17388fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** points to a buffer containing the name of the main database file. If the
17398fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** fourth parameter is 1, then the SQL statement that the third parameter
17408fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** points to has just been executed. Or, if the fourth parameter is 2, then
17418fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the connection being passed as the second parameter is being closed. The
17428fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** third parameter is passed NULL In this case.  An example of using this
17438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** configuration option can be seen in the "test_sqllog.c" source file in
17448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the canonical SQLite source tree.</dd>
17458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
17468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_CONFIG_MMAP_SIZE]]
17478fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dt>SQLITE_CONFIG_MMAP_SIZE
17488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
17498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** that are the default mmap size limit (the default setting for
17508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
17518fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The default setting can be overridden by each database connection using
17528fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** either the [PRAGMA mmap_size] command, or by using the
17538fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
17543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** will be silently truncated if necessary so that it does not exceed the
17553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** compile-time maximum mmap size set by the
17568fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
17578fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If either argument to this option is negative, then that argument is
17588fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** changed to its compile-time default.
17598fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
17608fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
17618fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
17623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
17633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
17643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
17658fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** that specifies the maximum size of the created heap.
17663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
17673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
17683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
17693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
17703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a pointer to an integer and writes into that integer the number of extra
17713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
17723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The amount of extra space required can change depending on the compiler,
17733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** target platform, and SQLite version.
17743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
17753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_CONFIG_PMASZ]]
17763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dt>SQLITE_CONFIG_PMASZ
17773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
17783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
17793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sorter to that integer.  The default minimum PMA Size is set by the
17803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
17813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to help with sort operations when multithreaded sorting
17823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is enabled (using the [PRAGMA threads] command) and the amount of content
17833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to be sorted exceeds the page size times the minimum of the
17843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [PRAGMA cache_size] setting and this value.
1785a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
1786a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
1787a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
1788a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
1789a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
1790a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
1791a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
1792a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
1793a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
1794a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
1795a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
1796a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
1797a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
1798a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1799a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
180090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CONFIG_PCACHE       14  /* no-op */
180190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
1802aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
180390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CONFIG_URI          17  /* int */
180490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
180590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
18068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
18078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
18088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
18098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
18103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
18113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
1812a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1813a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
181471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Database Connection Configuration Options
18157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1816a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These constants are the available integer configuration options that
1817a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be passed as the second argument to the [sqlite3_db_config()] interface.
18187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1819a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New configuration options may be added in future releases of SQLite.
1820a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Existing configuration options might be discontinued.  Applications
1821a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** should check the return code from [sqlite3_db_config()] to make sure that
1822a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the call worked.  ^The [sqlite3_db_config()] interface will return a
1823a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** non-zero [error code] if a discontinued or unsupported configuration option
1824a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is invoked.
1825a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
1826a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
1827a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1828a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd> ^This option takes three additional arguments that determine the
1829a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [lookaside memory allocator] configuration for the [database connection].
1830a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument (the third parameter to [sqlite3_db_config()] is a
183190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** pointer to a memory buffer to use for lookaside memory.
1832a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1833a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** may be NULL in which case SQLite will allocate the
1834a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1835a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** size of each lookaside buffer slot.  ^The third argument is the number of
1836a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** slots.  The size of the buffer in the first argument must be greater than
1837a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or equal to the product of the second and third arguments.  The buffer
1838a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must be aligned to an 8-byte boundary.  ^If the second argument to
1839a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1840de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
1841de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** configuration for a database connection can only be changed when that
1842de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** connection is not currently using lookaside memory, or in other words
1843de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** when the "current value" returned by
1844de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1845de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Any attempt to change the lookaside memory configuration when lookaside
1846de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** memory is in use leaves the configuration unchanged and returns
1847de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [SQLITE_BUSY].)^</dd>
18487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
184990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
185090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd> ^This option is used to enable or disable the enforcement of
185190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [foreign key constraints].  There should be two additional arguments.
185290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The first argument is an integer which is 0 to disable FK enforcement,
185390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** positive to enable FK enforcement or negative to leave FK enforcement
185490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** unchanged.  The second parameter is a pointer to an integer into which
185590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is written 0 or 1 to indicate whether FK enforcement is off or on
185690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** following this call.  The second parameter may be a NULL pointer, in
185790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** which case the FK enforcement setting is not reported back. </dd>
185890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
185990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
186090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
186190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** There should be two additional arguments.
186290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The first argument is an integer which is 0 to disable triggers,
186390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** positive to enable triggers or negative to leave the setting unchanged.
186490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The second parameter is a pointer to an integer into which
186590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is written 0 or 1 to indicate whether triggers are disabled or enabled
186690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** following this call.  The second parameter may be a NULL pointer, in
186790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** which case the trigger setting is not reported back. </dd>
186890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
1869a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
1870a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
187190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
187290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
187390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */
1874a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1875a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1876a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1877a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Enable Or Disable Extended Result Codes
18787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1879a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_extended_result_codes() routine enables or disables the
1880a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [extended result codes] feature of SQLite. ^The extended result
1881a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** codes are disabled by default for historical compatibility.
18827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
18833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_extended_result_codes(sqlite3*, int onoff);
18847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
18857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
1886a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Last Insert Rowid
18877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
18888fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
18898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** has a unique 64-bit signed
1890a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** integer key called the [ROWID | "rowid"]. ^The rowid is always available
18917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1892a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** names are not also used by explicitly declared columns. ^If
1893a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the table has a column of type [INTEGER PRIMARY KEY] then that column
18947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is another alias for the rowid.
18957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
18968fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the
18978fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** most recent successful [INSERT] into a rowid table or [virtual table]
18988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** on database connection D.
18998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^Inserts into [WITHOUT ROWID] tables are not recorded.
19008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If no successful [INSERT]s into rowid tables
19018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** have ever occurred on the database connection D,
19028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** then sqlite3_last_insert_rowid(D) returns zero.
19037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
190490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
190590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** method, then this routine will return the [rowid] of the inserted
190690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** row as long as the trigger or virtual table method is running.
190790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** But once the trigger or virtual table method ends, the value returned
190890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** by this routine reverts to what it was before the trigger or virtual
190990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** table method began.)^
19107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1911a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^An [INSERT] that fails due to a constraint violation is not a
1912a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** successful [INSERT] and does not change the value returned by this
1913a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
19147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and INSERT OR ABORT make no changes to the return value of this
1915a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine when their insertion fails.  ^(When INSERT OR REPLACE
19167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** encounters a constraint violation, it does not fail.  The
19177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** INSERT continues to completion after deleting rows that caused
19187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the constraint problem so INSERT OR REPLACE will always change
1919a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the return value of this interface.)^
19207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1921a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^For the purposes of this routine, an [INSERT] is considered to
19227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** be successful even if it is subsequently rolled back.
19237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1924a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This function is accessible to SQL statements via the
1925a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [last_insert_rowid() SQL function].
19267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1927a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If a separate thread performs a new [INSERT] on the same
1928a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database connection while the [sqlite3_last_insert_rowid()]
1929a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function is running and thus changes the last insert [rowid],
1930a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the value returned by [sqlite3_last_insert_rowid()] is
1931a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** unpredictable and might not equal either the old or the new
1932a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** last insert [rowid].
19337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
19343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_last_insert_rowid(sqlite3*);
19357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
19367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
1937a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Count The Number Of Rows Modified
19387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
19393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^This function returns the number of rows modified, inserted or
19403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** deleted by the most recently completed INSERT, UPDATE or DELETE
19413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** statement on the database connection specified by the only parameter.
19423fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Executing any other type of SQL statement does not modify the value
19433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** returned by this function.
19443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19453fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
19463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
19473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [foreign key actions] or [REPLACE] constraint resolution are not counted.
19483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Changes to a view that are intercepted by
19503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
19513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
19523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** DELETE statement run on a view is always zero. Only changes made to real
19533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** tables are counted.
19543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Things are more complicated if the sqlite3_changes() function is
19563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** executed while a trigger program is running. This may happen if the
19573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** program uses the [changes() SQL function], or if some other callback
19583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** function invokes sqlite3_changes() directly. Essentially:
19593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <ul>
19613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Before entering a trigger program the value returned by
19623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        sqlite3_changes() function is saved. After the trigger program
19633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        has finished, the original value is restored.)^
19643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19653fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
19663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        statement sets the value returned by sqlite3_changes()
19673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        upon completion as normal. Of course, this value will not include
19683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        any changes performed by sub-triggers, as the sqlite3_changes()
19693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**        value will be saved and restored after each sub-trigger has run.)^
19703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </ul>
19713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^This means that if the changes() SQL function (or similar) is used
19733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** by the first INSERT, UPDATE or DELETE statement within a trigger, it
19743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** returns the value as set when the calling statement began executing.
19753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If it is used by the second or subsequent such statement within a trigger
19763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** program, the value returned reflects the number of rows modified by the
19773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** previous INSERT, UPDATE or DELETE statement within the same trigger.
19787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1979a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also the [sqlite3_total_changes()] interface, the
1980a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [count_changes pragma], and the [changes() SQL function].
19817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
1982a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If a separate thread makes changes on the same database connection
1983a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** while [sqlite3_changes()] is running then the value returned
1984a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is unpredictable and not meaningful.
1985a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
19863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_changes(sqlite3*);
1987a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
1988a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
1989a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Total Number Of Rows Modified
1990a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
19913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^This function returns the total number of rows inserted, modified or
19923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
19933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** since the database connection was opened, including those executed as
19943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** part of trigger programs. ^Executing any other type of SQL statement
19953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** does not affect the value returned by sqlite3_total_changes().
19963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
19973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Changes made as part of [foreign key actions] are included in the
19983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** count, but those made as part of REPLACE constraint resolution are
19993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
20003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** are not counted.
20013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
2002a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also the [sqlite3_changes()] interface, the
2003a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [count_changes pragma], and the [total_changes() SQL function].
2004a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2005a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If a separate thread makes changes on the same database connection
2006a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** while [sqlite3_total_changes()] is running then the value
2007a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned is unpredictable and not meaningful.
20087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
20093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_total_changes(sqlite3*);
20107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
20117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2012a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Interrupt A Long-Running Query
20137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2014a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This function causes any pending database operation to abort and
20157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** return at its earliest opportunity. This routine is typically
20167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** called in response to a user action such as pressing "Cancel"
20177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or Ctrl-C where the user wants a long query operation to halt
20187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** immediately.
20197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2020a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^It is safe to call this routine from a thread different from the
20217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** thread that is currently running the database operation.  But it
2022a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not safe to call this routine with a [database connection] that
20237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is closed or might close before sqlite3_interrupt() returns.
20247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2025a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an SQL operation is very nearly finished at the time when
2026a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_interrupt() is called, then it might not have an opportunity
2027a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to be interrupted and might continue to completion.
2028a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2029a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2030a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2031a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that is inside an explicit transaction, then the entire transaction
2032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will be rolled back automatically.
2033a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_interrupt(D) call is in effect until all currently running
2035a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL statements on [database connection] D complete.  ^Any new SQL statements
2036a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that are started after the sqlite3_interrupt() call and before the
2037a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** running statements reaches zero are interrupted as if they had been
2038a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2039a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that are started after the running statement count reaches zero are
2040a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not effected by the sqlite3_interrupt().
2041a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2042a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL statements is a no-op and has no effect on SQL statements
2043a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that are started after the sqlite3_interrupt() call returns.
2044a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2045a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If the database connection closes while [sqlite3_interrupt()]
2046a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is running then bad things will likely happen.
20477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
20483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_interrupt(sqlite3*);
20497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
20507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2051a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Determine If An SQL Statement Is Complete
20527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2053a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These routines are useful during command-line input to determine if the
2054a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** currently entered text seems to form a complete SQL statement or
20557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** if additional input is needed before sending the text into
2056a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite for parsing.  ^These routines return 1 if the input string
2057a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** appears to be a complete SQL statement.  ^A statement is judged to be
2058a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** complete if it ends with a semicolon token and is not a prefix of a
2059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
20607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** string literals or quoted identifier names or comments are not
20617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** independent tokens (they are part of the token in which they are
2062a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** embedded) and thus do not count as a statement terminator.  ^Whitespace
2063a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and comments that follow the final semicolon are ignored.
20647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2065a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines return 0 if the statement is incomplete.  ^If a
2066a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory allocation fails, then SQLITE_NOMEM is returned.
20677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2068a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines do not parse the SQL statements thus
2069a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will not detect syntactically incorrect SQL.
20707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2071a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2072a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2073a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** automatically by sqlite3_complete16().  If that initialization fails,
2074a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the return value from sqlite3_complete16() will be non-zero
2075a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** regardless of whether or not the input SQL is complete.)^
20767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2077a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The input to [sqlite3_complete()] must be a zero-terminated
2078a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** UTF-8 string.
20797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2080a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The input to [sqlite3_complete16()] must be a zero-terminated
2081a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** UTF-16 string in native byte order.
20827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
20833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_complete(const char *sql);
20843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_complete16(const void *sql);
20857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
20867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2087a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
20883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** KEYWORDS: {busy-handler callback} {busy handler}
2089a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
20909bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
20919bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** that might be invoked with argument P whenever
20929bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** an attempt is made to access a database table associated with
20939bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [database connection] D when another thread
20949bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** or process has the table locked.
20959bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** The sqlite3_busy_handler() interface is used to implement
20969bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
20977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
20989bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** ^If the busy callback is NULL, then [SQLITE_BUSY]
2099a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is returned immediately upon encountering the lock.  ^If the busy callback
2100a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not NULL, then the callback might be invoked with two arguments.
2101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2102a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument to the busy handler is a copy of the void* pointer which
2103a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is the third argument to sqlite3_busy_handler().  ^The second argument to
2104a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the busy handler callback is the number of times that the busy handler has
21053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** been invoked previously for the same locking event.  ^If the
21067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** busy callback returns 0, then no additional attempts are made to
21079bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** access the database and [SQLITE_BUSY] is returned
21089bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** to the application.
2109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the callback returns non-zero, then another attempt
21109bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** is made to access the database and the cycle repeats.
21117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The presence of a busy handler does not guarantee that it will be invoked
2113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when there is lock contention. ^If SQLite determines that invoking the busy
2114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
21159bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** to the application instead of invoking the
21169bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** busy handler.
21177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Consider a scenario where one process is holding a read lock that
21187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** it is trying to promote to a reserved lock and
21197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a second process is holding a reserved lock that it is trying
21207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to promote to an exclusive lock.  The first process cannot proceed
21217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** because it is blocked by the second and the second process cannot
21227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** proceed because it is blocked by the first.  If both processes
21237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** invoke the busy handlers, neither will make any progress.  Therefore,
21247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
21257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** will induce the first process to release its read lock and allow
21267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the second process to proceed.
21277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2128a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The default busy callback is NULL.
21297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2130a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(There can only be a single busy handler defined for each
2131a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection].  Setting a new busy handler clears any
2132a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
21339bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** or evaluating [PRAGMA busy_timeout=N] will change the
21349bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** busy handler and thus clear any previously set busy handler.
21357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2136a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The busy callback should not take any actions which modify the
21379bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** database connection that invoked the busy handler.  In other words,
21389bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** the busy handler is not reentrant.  Any such actions
2139a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** result in undefined behavior.
2140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A busy handler must not close the database connection
2142a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [prepared statement] that invoked the busy handler.
21437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
21443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
21457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
21467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2147a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Set A Busy Timeout
21487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2149a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2150a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for a specified amount of time when a table is locked.  ^The handler
2151a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will sleep multiple times until at least "ms" milliseconds of sleeping
2152a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2153a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the handler returns 0 which causes [sqlite3_step()] to return
21549bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [SQLITE_BUSY].
21557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2156a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Calling this routine with an argument less than or equal to zero
21577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** turns off all busy handlers.
21587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2159a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(There can only be a single busy handler for a particular
21603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [database connection] at any given moment.  If another busy handler
2161a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** was defined  (using [sqlite3_busy_handler()]) prior to calling
2162a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this routine, that other busy handler is cleared.)^
21639bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown**
21649bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** See also:  [PRAGMA busy_timeout]
21657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
21663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_busy_timeout(sqlite3*, int ms);
21677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
21687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2169a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Convenience Routines For Running Queries
21707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
217195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** This is a legacy interface that is preserved for backwards compatibility.
217295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** Use of this interface is not recommended.
217395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
21747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Definition: A <b>result table</b> is memory data structure created by the
21757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_get_table()] interface.  A result table records the
21767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** complete query results from one or more queries.
21777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
21787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The table conceptually has a number of rows and columns.  But
21797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** these numbers are not part of the result table itself.  These
21807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** numbers are obtained separately.  Let N be the number of rows
21817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and M be the number of columns.
21827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2183a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A result table is an array of pointers to zero-terminated UTF-8 strings.
2184a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** There are (N+1)*M elements in the array.  The first M pointers point
2185a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to zero-terminated strings that  contain the names of the columns.
2186a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The remaining entries all point to query results.  NULL values result
2187a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2188a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** string representation as returned by [sqlite3_column_text()].
21897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2190a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A result table might consist of one or more memory allocations.
21917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** It is not safe to pass a result table directly to [sqlite3_free()].
21927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** A result table should be deallocated using [sqlite3_free_table()].
21937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
219495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^(As an example of the result table format, suppose a query result
21957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is as follows:
21967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
21977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
21987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        Name        | Age
21997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        -----------------------
22007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        Alice       | 43
22017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        Bob         | 28
22027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        Cindy       | 21
22037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
22047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
22057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** There are two column (M==2) and three rows (N==3).  Thus the
22067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** result table has 8 entries.  Suppose the result table is stored
22077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in an array names azResult.  Then azResult holds this content:
22087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
22097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
22107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;0] = "Name";
22117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;1] = "Age";
22127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;2] = "Alice";
22137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;3] = "43";
22147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;4] = "Bob";
22157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;5] = "28";
22167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;6] = "Cindy";
22177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**        azResult&#91;7] = "21";
221895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** </pre></blockquote>)^
22197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2220a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_get_table() function evaluates one or more
22217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** semicolon-separated SQL statements in the zero-terminated UTF-8
2222a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** string of its 2nd parameter and returns a result table to the
22237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** pointer given in its 3rd parameter.
22247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2225a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** After the application has finished with the result from sqlite3_get_table(),
222695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** it must pass the result table pointer to sqlite3_free_table() in order to
2227a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** release the memory that was malloced.  Because of the way the
22287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2229a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function must not try to call [sqlite3_free()] directly.  Only
22307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_free_table()] is able to release the memory properly and safely.
22317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
223295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** The sqlite3_get_table() interface is implemented as a wrapper around
22337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
22347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to any internal data structures of SQLite.  It uses only the public
22357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface defined here.  As a consequence, errors that occur in the
22367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** wrapper layer outside of the internal [sqlite3_exec()] call are not
22377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** reflected in subsequent calls to [sqlite3_errcode()] or
223895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** [sqlite3_errmsg()].
2239a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
22403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_get_table(
2241a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3 *db,          /* An open database */
2242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const char *zSql,     /* SQL to be evaluated */
2243a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  char ***pazResult,    /* Results of the query */
2244a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int *pnRow,           /* Number of result rows written here */
2245a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int *pnColumn,        /* Number of result columns written here */
2246a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  char **pzErrmsg       /* Error msg written here */
22477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
22483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_free_table(char **result);
22497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
22507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2251a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Formatted String Printing Functions
22527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2253a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These routines are work-alikes of the "printf()" family of functions
22547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** from the standard C library.
22553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** These routines understand most of the common K&R formatting options,
22563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** plus some additional non-standard formats, detailed below.
22573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Note that some of the more obscure formatting options from recent
22583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** C-library standards are omitted from this implementation.
22597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2260a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
22617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** results into memory obtained from [sqlite3_malloc()].
22627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The strings returned by these two routines should be
2263a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** released by [sqlite3_free()].  ^Both routines return a
22647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
22657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** memory to hold the resulting string.
22667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
226790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
22687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the standard C library.  The result is written into the
22697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** buffer supplied as the second parameter whose size is given by
22707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the first parameter. Note that the order of the
2271a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** first two parameters is reversed from snprintf().)^  This is an
22727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** historical accident that cannot be fixed without breaking
2273a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** backwards compatibility.  ^(Note also that sqlite3_snprintf()
22747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** returns a pointer to its buffer instead of the number of
2275a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** characters actually written into the buffer.)^  We admit that
22767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the number of characters written would be a more useful return
22777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** value but we cannot change the implementation of sqlite3_snprintf()
22787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** now without breaking compatibility.
22797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2280a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2281a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** guarantees that the buffer is always zero-terminated.  ^The first
22827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** parameter "n" is the total size of the buffer, including space for
22837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the zero terminator.  So the longest string that can be completely
22847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** written will be n-1 characters.
22857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
228690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
228790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
22887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines all implement some additional formatting
22897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** options that are useful for constructing SQL statements.
2290a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** All of the usual printf() formatting options apply.  In addition, there
22913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is are "%q", "%Q", "%w" and "%z" options.
22927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
229390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(The %q option works like %s in that it substitutes a nul-terminated
22947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** string from the argument list.  But %q also doubles every '\'' character.
2295a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** %q is designed for use inside a string literal.)^  By doubling each '\''
22967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** character it escapes that character and allows it to be inserted into
22977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the string.
22987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2299a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** For example, assume the string variable zText contains text as follows:
23007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
23027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  char *zText = "It's a happy day!";
23037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
23047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** One can use this text in an SQL statement as follows:
23067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
23087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
23097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  sqlite3_exec(db, zSQL, 0, 0, 0);
23107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  sqlite3_free(zSQL);
23117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
23127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Because the %q format string is used, the '\'' character in zText
23147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is escaped and the SQL generated is as follows:
23157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
23177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  INSERT INTO table1 VALUES('It''s a happy day!')
23187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
23197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This is correct.  Had we used %s instead of %q, the generated SQL
23217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** would have looked like this:
23227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
23247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  INSERT INTO table1 VALUES('It's a happy day!');
23257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
23267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2327a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This second example is an SQL syntax error.  As a general rule you should
2328a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** always use %q instead of %s when inserting text into a string literal.
23297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The %Q option works like %q except it also adds single quotes around
2331a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the outside of the total string.  Additionally, if the parameter in the
2332a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
2333a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** single quotes).)^  So, for example, one could say:
23347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote><pre>
23367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
23377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  sqlite3_exec(db, zSQL, 0, 0, 0);
23387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  sqlite3_free(zSQL);
23397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </pre></blockquote>
23407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The code above will render a correct SQL statement in the zSQL
23427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** variable even if the zText variable is a NULL pointer.
23437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The "%w" formatting option is like "%q" except that it expects to
23453fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** be contained within double-quotes instead of single quotes, and it
23463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** escapes the double-quote character instead of the single-quote
23473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** character.)^  The "%w" formatting option is intended for safely inserting
23483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** table and column names into a constructed SQL statement.
23493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
2350a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The "%z" formatting option works like "%s" but with the
23517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** addition that after the string has been read and copied into
2352a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the result, [sqlite3_free()] is called on the input string.)^
23537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
23543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API char *SQLITE_CDECL sqlite3_mprintf(const char*,...);
23553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API char *SQLITE_STDCALL sqlite3_vmprintf(const char*, va_list);
23563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API char *SQLITE_CDECL sqlite3_snprintf(int,char*,const char*, ...);
23573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API char *SQLITE_STDCALL sqlite3_vsnprintf(int,char*,const char*, va_list);
23587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
23597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2360a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Memory Allocation Subsystem
23617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2362a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The SQLite core uses these three routines for all of its own
23637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** internal memory allocation needs. "Core" in the previous sentence
23647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** does not include operating-system specific VFS implementation.  The
2365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Windows VFS uses native malloc() and free() for some operations.
23667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2367a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_malloc() routine returns a pointer to a block
23687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of memory at least N bytes in length, where N is the parameter.
2369a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_malloc() is unable to obtain sufficient free
2370a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory, it returns a NULL pointer.  ^If the parameter N to
23717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
23727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a NULL pointer.
23737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_malloc64(N) routine works just like
23753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
23763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of a signed 32-bit integer.
23773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
2378a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Calling sqlite3_free() with a pointer previously returned
23797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2380a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that it might be reused.  ^The sqlite3_free() routine is
23817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a no-op if is called with a NULL pointer.  Passing a NULL pointer
23827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to sqlite3_free() is harmless.  After being freed, memory
23837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** should neither be read nor written.  Even reading previously freed
23847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** memory might result in a segmentation fault or other severe error.
23857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Memory corruption, a segmentation fault, or other severe error
23867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** might result if sqlite3_free() is called with a non-NULL pointer that
2387a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** was not obtained from sqlite3_malloc() or sqlite3_realloc().
23887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
23893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_realloc(X,N) interface attempts to resize a
23903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** prior memory allocation X to be at least N bytes.
23913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the X parameter to sqlite3_realloc(X,N)
23927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is a NULL pointer then its behavior is identical to calling
23933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_malloc(N).
23943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the N parameter to sqlite3_realloc(X,N) is zero or
23957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** negative then the behavior is exactly the same as calling
23963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_free(X).
23973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
23983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of at least N bytes in size or NULL if insufficient memory is available.
2399a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If M is the size of the prior allocation, then min(N,M) bytes
24007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the prior allocation are copied into the beginning of buffer returned
24013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** by sqlite3_realloc(X,N) and the prior allocation is freed.
24023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
24033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** prior allocation is not freed.
24043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
24053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_realloc64(X,N) interfaces works the same as
24063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
24073fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of a 32-bit signed integer.
24083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
24093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
24103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
24113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_msize(X) returns the size of that memory allocation in bytes.
24123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The value returned by sqlite3_msize(X) might be larger than the number
24133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of bytes requested when X was allocated.  ^If X is a NULL pointer then
24143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_msize(X) returns zero.  If X points to something that is not
24153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the beginning of memory allocation, or if it points to a formerly
24163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** valid memory allocation that has now been freed, then the behavior
24173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of sqlite3_msize(X) is undefined and possibly harmful.
24183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
24193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
24203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_malloc64(), and sqlite3_realloc64()
2421de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** is always aligned to at least an 8 byte boundary, or to a
2422de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2423de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** option is used.
24247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
24257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** In SQLite version 3.5.0 and 3.5.1, it was possible to define
24267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
24277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** implementation of these routines to be omitted.  That capability
2428a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is no longer provided.  Only built-in memory allocators can be used.
24297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
24308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Prior to SQLite version 3.7.10, the Windows OS interface layer called
24317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the system malloc() and free() directly when converting
24327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** filenames between the UTF-8 encoding used by SQLite
2433a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and whatever filename encoding is used by the particular Windows
24348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** installation.  Memory allocation errors were detected, but
24358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** they were reported back as [SQLITE_CANTOPEN] or
24367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
24377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2438a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2439a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must be either NULL or else pointers obtained from a prior
2440a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2441a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not yet been released.
24427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2443a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The application must not read or write any part of
2444a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a block of memory after it has been released using
2445a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_free()] or [sqlite3_realloc()].
24467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
24473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_malloc(int);
24483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_malloc64(sqlite3_uint64);
24493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_realloc(void*, int);
24503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_realloc64(void*, sqlite3_uint64);
24513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_free(void*);
24523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_uint64 SQLITE_STDCALL sqlite3_msize(void*);
24537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
24547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2455a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Memory Allocator Statistics
24567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
24577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite provides these two interfaces for reporting on the status
24587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2459a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines, which form the built-in memory allocation subsystem.
2460a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2461a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_memory_used()] routine returns the number of bytes
2462a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of memory currently outstanding (malloced but not freed).
2463a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_memory_highwater()] routine returns the maximum
2464a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value of [sqlite3_memory_used()] since the high-water mark
2465a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2466a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_memory_highwater()] include any overhead
2467a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** added by SQLite in its implementation of [sqlite3_malloc()],
2468a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** but not overhead added by the any underlying system library
2469a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines that [sqlite3_malloc()] may call.
2470a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2471a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The memory high-water mark is reset to the current value of
2472a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_memory_used()] if and only if the parameter to
2473a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_memory_highwater()] is true.  ^The value returned
2474a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by [sqlite3_memory_highwater(1)] is the high-water mark
2475a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prior to the reset.
24767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
24773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_used(void);
24783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_highwater(int resetFlag);
24797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
24807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2481a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Pseudo-Random Number Generator
24827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
24837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2484a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** select random [ROWID | ROWIDs] when inserting new records into a table that
2485a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** already uses the largest possible [ROWID].  The PRNG is also used for
24867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the build-in random() and randomblob() SQL functions.  This interface allows
2487a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** applications to access the same PRNG for other purposes.
24887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2489a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A call to this routine stores N bytes of randomness into buffer P.
24903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The P parameter can be a NULL pointer.
24917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
24928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If this routine has not been previously called or if the previous
24933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** call had N less than one or a NULL pointer for P, then the PRNG is
24943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** seeded using randomness obtained from the xRandomness method of
24953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the default [sqlite3_vfs] object.
24963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the previous call to this routine had an N of 1 or more and a
24973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** non-NULL P then the pseudo-randomness is generated
24987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** internally and without recourse to the [sqlite3_vfs] xRandomness
24997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** method.
25007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
25013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_randomness(int N, void *P);
25027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
25037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2504a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Compile-Time Authorization Callbacks
25057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
250690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^This routine registers an authorizer callback with a particular
25077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [database connection], supplied in the first argument.
2508a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The authorizer callback is invoked as SQL statements are being compiled
25097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2510a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  ^At various
25117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** points during the compilation process, as logic is being created
25127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to perform various actions, the authorizer callback is invoked to
2513a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** see if those actions are allowed.  ^The authorizer callback should
25147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
25157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** specific action but allow the SQL statement to continue to be
25167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2517a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** rejected with an error.  ^If the authorizer callback returns
25187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2519a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the [sqlite3_prepare_v2()] or equivalent call that triggered
25207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the authorizer will fail with an error message.
25217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
25227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** When the callback returns [SQLITE_OK], that means the operation
2523a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** requested is ok.  ^When the callback returns [SQLITE_DENY], the
25247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_prepare_v2()] or equivalent call that triggered the
25257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** authorizer will fail with an error message explaining that
2526a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** access is denied.
2527a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2528a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first parameter to the authorizer callback is a copy of the third
2529a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2530a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the callback is an integer [SQLITE_COPY | action code] that specifies
2531a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the particular action to be authorized. ^The third through sixth parameters
2532a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the callback are zero-terminated strings that contain additional
2533a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** details about the action to be authorized.
2534a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2535a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the action code is [SQLITE_READ]
25367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and the callback returns [SQLITE_IGNORE] then the
25377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [prepared statement] statement is constructed to substitute
25387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a NULL value in place of the table column that would have
25397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
25407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** return can be used to deny an untrusted user access to individual
25417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** columns of a table.
2542a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the action code is [SQLITE_DELETE] and the callback returns
2543a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2544a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [truncate optimization] is disabled and all rows are deleted individually.
25457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
25467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** An authorizer is used when [sqlite3_prepare | preparing]
2547a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL statements from an untrusted source, to ensure that the SQL statements
2548a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** do not try to access data they are not allowed to see, or that they do not
2549a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** try to execute malicious statements that damage the database.  For
25507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** example, an application may allow a user to enter arbitrary
25517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQL queries for evaluation by a database.  But the application does
25527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** not want the user to be able to make arbitrary changes to the
25537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** database.  An authorizer could then be put in place while the
25547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** user-entered SQL is being [sqlite3_prepare | prepared] that
25557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** disallows everything except [SELECT] statements.
25567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
25577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Applications that need to process SQL from untrusted sources
25587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** might also consider lowering resource limits using [sqlite3_limit()]
25597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and limiting database size using the [max_page_count] [PRAGMA]
25607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in addition to using an authorizer.
25617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2562a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Only a single authorizer can be in place on a database connection
25637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** at a time.  Each call to sqlite3_set_authorizer overrides the
2564a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** previous call.)^  ^Disable the authorizer by installing a NULL callback.
25657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The authorizer is disabled by default.
25667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2567a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The authorizer callback must not do anything that will modify
2568a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the database connection that invoked the authorizer callback.
2569a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2570a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database connections for the meaning of "modify" in this paragraph.
25717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2572a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2573a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** statement might be re-prepared during [sqlite3_step()] due to a
2574a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** schema change.  Hence, the application should ensure that the
2575a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** correct authorizer callback remains in place during the [sqlite3_step()].
25767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2577a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Note that the authorizer callback is invoked only during
2578a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare()] or its variants.  Authorization is not
2579a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** performed during statement evaluation in [sqlite3_step()], unless
2580a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** as stated in the previous paragraph, sqlite3_step() invokes
2581a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_prepare_v2() to reprepare a statement after a schema change.
25827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
25833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_set_authorizer(
25847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
25857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
25867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *pUserData
25877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
25887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
25897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2590a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Authorizer Return Codes
25917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
25927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The [sqlite3_set_authorizer | authorizer callback function] must
25937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** return either [SQLITE_OK] or one of these two constants in order
25947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to signal SQLite whether or not the action is permitted.  See the
25957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_set_authorizer | authorizer documentation] for additional
25967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** information.
259790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
25989bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
25999bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** returned from the [sqlite3_vtab_on_conflict()] interface.
26007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
26017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
26027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
26037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
26047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2605a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Authorizer Action Codes
26067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
26077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The [sqlite3_set_authorizer()] interface registers a callback function
2608a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that is invoked to authorize certain SQL statement actions.  The
26097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** second parameter to the callback is an integer code that specifies
26107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** what action is being authorized.  These are the integer action codes that
26117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the authorizer callback may be passed.
26127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2613a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These action code values signify what kind of operation is to be
26147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** authorized.  The 3rd and 4th parameters to the authorization
26157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** callback function will be parameters or NULL depending on which of these
2616a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** codes is used as the second parameter.  ^(The 5th parameter to the
2617a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** authorizer callback is the name of the database ("main", "temp",
2618a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
26197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is the name of the inner-most trigger or view that is responsible for
2620a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the access attempt or NULL if this access attempt is directly from
26217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** top-level SQL code.
26227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
26237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/******************************************* 3rd ************ 4th ***********/
26247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
26257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
26267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
26277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
26287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
26297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
26307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
26317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
26327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DELETE                9   /* Table Name      NULL            */
26337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
26347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
26357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
26367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
26377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
26387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
26397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
26407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
26417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INSERT               18   /* Table Name      NULL            */
26427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
26437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_READ                 20   /* Table Name      Column Name     */
26447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_SELECT               21   /* NULL            NULL            */
2645a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
26467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
26477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ATTACH               24   /* Filename        NULL            */
26487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DETACH               25   /* Database Name   NULL            */
26497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
26507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_REINDEX              27   /* Index Name      NULL            */
26517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
26527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
26537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
2654a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
2655a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
26567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_COPY                  0   /* No longer used */
26578fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
26587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
26597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2660a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Tracing And Profiling Functions
26617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
26627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines register callback functions that can be used for
26637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** tracing and profiling the execution of SQL statements.
26647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2665a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The callback function registered by sqlite3_trace() is invoked at
26667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** various times when an SQL statement is being run by [sqlite3_step()].
2667a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2668a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL statement text as the statement first begins executing.
2669a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Additional sqlite3_trace() callbacks might occur
2670a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** as each triggered subprogram is entered.  The callbacks for triggers
2671a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** contain a UTF-8 SQL comment that identifies the trigger.)^
2672a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
26738fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
26748fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the length of [bound parameter] expansion in the output of sqlite3_trace().
26758fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
2676a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The callback function registered by sqlite3_profile() is invoked
2677a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** as each SQL statement finishes.  ^The profile callback contains
26787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the original statement text and an estimate of wall-clock time
2679de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** of how long that statement took to run.  ^The profile callback
2680de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** time is in units of nanoseconds, however the current implementation
2681de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** is only capable of millisecond resolution so the six least significant
2682de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** digits in the time are meaningless.  Future versions of SQLite
2683de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** might provide greater resolution on the profiler callback.  The
2684de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** sqlite3_profile() function is considered experimental and is
2685de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** subject to change in future versions of SQLite.
26867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
26873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
26883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_EXPERIMENTAL void *SQLITE_STDCALL sqlite3_profile(sqlite3*,
26897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
26907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
26917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2692a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Query Progress Callbacks
26937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2694de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
2695de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** function X to be invoked periodically during long running calls to
2696de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
2697de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** database connection D.  An example use for this
26987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface is to keep a GUI updated during a large query.
26997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2700de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The parameter P is passed through as the only parameter to the
27018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** callback function X.  ^The parameter N is the approximate number of
2702de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [virtual machine instructions] that are evaluated between successive
27038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** invocations of the callback X.  ^If N is less than one then the progress
27048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** handler is disabled.
2705de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
2706de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Only a single progress handler may be defined at one time per
2707de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [database connection]; setting a new progress handler cancels the
2708de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** old one.  ^Setting parameter X to NULL disables the progress handler.
2709de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The progress handler is also disabled by setting N to a value less
2710de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** than 1.
2711de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
2712a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the progress callback returns non-zero, the operation is
27137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interrupted.  This feature can be used to implement a
2714a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** "Cancel" button on a GUI progress dialog box.
27157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2716de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The progress handler callback must not do anything that will modify
2717a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the database connection that invoked the progress handler.
2718a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2719a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database connections for the meaning of "modify" in this paragraph.
27207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
27217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
27223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
27237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
27247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
2725a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Opening A New Database Connection
2726a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
272790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^These routines open an SQLite database file as specified by the
2728a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** filename argument. ^The filename argument is interpreted as UTF-8 for
2729a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2730a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** order for sqlite3_open16(). ^(A [database connection] handle is usually
2731a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned in *ppDb, even if an error occurs.  The only exception is that
2732a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2733a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
2734a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** object.)^ ^(If the database is opened (and/or created) successfully, then
2735a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
2736a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
2737a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an English language description of the error following a failure of any
2738a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the sqlite3_open() routines.
2739a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
27403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The default encoding will be UTF-8 for databases created using
27413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
27423fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** created using sqlite3_open16() will be UTF-16 in the native byte order.
27437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
27447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Whether or not an error occurs when it is opened, resources
2745a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** associated with the [database connection] handle should be released by
2746a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** passing it to [sqlite3_close()] when it is no longer required.
27477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2748a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_open_v2() interface works like sqlite3_open()
2749a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** except that it accepts two additional parameters for additional control
2750a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** over the new database connection.  ^(The flags parameter to
2751a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_open_v2() can take one of
2752a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the following three values, optionally combined with the
2753a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
275490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
27557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2756a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
2757a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
2758a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The database is opened in read-only mode.  If the database does not
2759a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** already exist, an error is returned.</dd>)^
2760a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2761a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
2762a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The database is opened for reading and writing if possible, or reading
2763a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** only if the file is write protected by the operating system.  In either
2764a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** case the database must already exist, otherwise an error is returned.</dd>)^
2765a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2766a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
276790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>The database is opened for reading and writing, and is created if
2768a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it does not already exist. This is the behavior that is always used for
2769a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_open() and sqlite3_open16().</dd>)^
2770a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
2771a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2772a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If the 3rd parameter to sqlite3_open_v2() is not one of the
277390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** combinations shown above optionally combined with other
277490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
2775a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the behavior is undefined.
27767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2777a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
2778a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** opens in the multi-thread [threading mode] as long as the single-thread
2779a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** mode has not been set at compile-time or start-time.  ^If the
2780a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
2781a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the serialized [threading mode] unless single-thread was
2782a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** previously selected at compile-time or start-time.
2783a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
2784a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** eligible to use [shared cache mode], regardless of whether or not shared
2785a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
2786a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
2787a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** participate in [shared cache mode] even if it is enabled.
2788a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
278990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The fourth parameter to sqlite3_open_v2() is the name of the
279090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_vfs] object that defines the operating system interface that
279190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the new database connection should use.  ^If the fourth parameter is
279290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a NULL pointer then the default [sqlite3_vfs] object is used.
279390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
2794a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the filename is ":memory:", then a private, temporary in-memory database
2795a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is created for the connection.  ^This in-memory database will vanish when
2796a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the database connection is closed.  Future versions of SQLite might
2797a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** make use of additional special filenames that begin with the ":" character.
2798a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** It is recommended that when a database filename actually does begin with
2799a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a ":" character you should prefix the filename with a pathname such as
2800a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** "./" to avoid ambiguity.
2801a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
2802a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the filename is an empty string, then a private, temporary
2803a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on-disk database will be created.  ^This private database will be
28047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** automatically deleted as soon as the database connection is closed.
28057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
280690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
280790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
280890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^If [URI filename] interpretation is enabled, and the filename argument
280990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** begins with "file:", then the filename is interpreted as a URI. ^URI
281090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
281190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** set in the fourth argument to sqlite3_open_v2(), or if it has
281290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** been enabled globally using the [SQLITE_CONFIG_URI] option with the
281390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
281490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** As of SQLite version 3.7.7, URI filename interpretation is turned off
281590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** by default, but future releases of SQLite might enable URI filename
281690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** interpretation by default.  See "[URI filenames]" for additional
281790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** information.
281890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
281990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** URI filenames are parsed according to RFC 3986. ^If the URI contains an
282090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** authority, then it must be either an empty string or the string
282190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** "localhost". ^If the authority is not an empty string or "localhost", an
282290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** error is returned to the caller. ^The fragment component of a URI, if
282390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** present, is ignored.
282490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
282590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^SQLite uses the path component of the URI as the name of the disk file
282690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** which contains the database. ^If the path begins with a '/' character,
282790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** then it is interpreted as an absolute path. ^If the path does not begin
282890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** with a '/' (meaning that the authority section is omitted from the URI)
282990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** then the path is interpreted as a relative path.
28303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(On windows, the first component of an absolute path
28313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a drive specification (e.g. "C:").)^
283290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
283390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[core URI query parameters]]
283490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The query component of a URI may contain parameters that are interpreted
283590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** either by SQLite itself, or by a [VFS | custom VFS implementation].
28363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** SQLite and its built-in [VFSes] interpret the
28373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** following query parameters:
283890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
283990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <ul>
284090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
284190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     a VFS object that provides the operating system interface that should
284290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     be used to access the database file on disk. ^If this option is set to
284390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     an empty string the default VFS object is used. ^Specifying an unknown
284490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
284590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     present, then the VFS specified by the option takes precedence over
284690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     the value passed as the fourth parameter to sqlite3_open_v2().
284790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
28488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
28498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     "rwc", or "memory". Attempting to set it to any other value is
28508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     an error)^.
285190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     ^If "ro" is specified, then the database is opened for read-only
285290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
28538fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     third argument to sqlite3_open_v2(). ^If the mode option is set to
285490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     "rw", then the database is opened for read-write (but not create)
285590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
285690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     been set. ^Value "rwc" is equivalent to setting both
28578fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
28588fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     set to "memory" then a pure [in-memory database] that never reads
28598fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     or writes from disk is used. ^It is an error to specify a value for
28608fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     the mode parameter that is less restrictive than that specified by
28618fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     the flags passed in the third parameter to sqlite3_open_v2().
286290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
286390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
286490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     "private". ^Setting it to "shared" is equivalent to setting the
286590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
286690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
286790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
286890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
28698fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**     a URI filename, its value overrides any behavior requested by setting
287090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
28711c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
28723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
28731c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     [powersafe overwrite] property does or does not apply to the
28743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**     storage media on which the database file resides.
28751c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
28761c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
28771c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     which if set disables file locking in rollback journal modes.  This
28781c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     is useful for accessing a database on a filesystem that does not
28791c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     support locking.  Caution:  Database corruption might result if two
28801c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     or more processes write to the same database and any one of those
28811c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     processes uses nolock=1.
28821c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
28831c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
28841c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     parameter that indicates that the database file is stored on
28851c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     read-only media.  ^When immutable is set, SQLite assumes that the
28861c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     database file cannot be changed, even by a process with higher
28871c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     privilege, and so the database is opened read-only and all locking
28881c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     and change detection is disabled.  Caution: Setting the immutable
28891c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     property on a database file that does in fact change can result
28901c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
28911c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**     See also: [SQLITE_IOCAP_IMMUTABLE].
28921c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
289390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </ul>
289490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
289590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^Specifying an unknown parameter in the query component of a URI is not an
289690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** error.  Future versions of SQLite might understand additional query
289790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** parameters.  See "[query parameters with special meaning to SQLite]" for
289890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** additional information.
289990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
290090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[URI filename examples]] <h3>URI filename examples</h3>
290190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
290290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <table border="1" align=center cellpadding=5>
290390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><th> URI filenames <th> Results
290490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td> file:data.db <td>
290590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          Open the file "data.db" in the current directory.
290690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td> file:/home/fred/data.db<br>
290790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          file:///home/fred/data.db <br>
290890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          file://localhost/home/fred/data.db <br> <td>
290990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          Open the database file "/home/fred/data.db".
291090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td> file://darkstar/home/fred/data.db <td>
291190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          An error. "darkstar" is not a recognized authority.
291290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td style="white-space:nowrap">
291390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
291490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
291590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          C:. Note that the %20 escaping in this example is not strictly
291690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          necessary - space characters can be used literally
291790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          in URI filenames.
291890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td> file:data.db?mode=ro&cache=private <td>
291990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          Open file "data.db" in the current directory for read-only access.
292090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          Regardless of whether or not shared-cache mode is enabled by
292190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          default, use a private cache.
29221c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
29231c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
29241c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**          that uses dot-files in place of posix advisory locking.
292590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <tr><td> file:data.db?mode=readonly <td>
292690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**          An error. "readonly" is not a valid option for the "mode" parameter.
292790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </table>
292890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
292990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^URI hexadecimal escape sequences (%HH) are supported within the path and
293090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** query components of a URI. A hexadecimal escape sequence consists of a
293190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** percent sign - "%" - followed by exactly two hexadecimal digits
293290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** specifying an octet value. ^Before the path or query components of a
293390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** URI filename are interpreted, they are encoded using UTF-8 and all
293490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** hexadecimal escape sequences replaced by a single byte containing the
293590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** corresponding octet. If this process generates an invalid UTF-8 encoding,
293690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the results are undefined.
29377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
2938a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>Note to Windows users:</b>  The encoding used for the filename argument
2939a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
29407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** codepage is currently defined.  Filenames containing international
29417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** characters must be converted to UTF-8 prior to passing them into
2942a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_open() or sqlite3_open_v2().
29438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
29448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
29458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
29468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** features that require the use of temporary files may fail.
29478fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
29488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** See also: [sqlite3_temp_directory]
29497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
29503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_open(
29517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *filename,   /* Database filename (UTF-8) */
29527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 **ppDb          /* OUT: SQLite db handle */
29537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
29543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_open16(
29557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *filename,   /* Database filename (UTF-16) */
29567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 **ppDb          /* OUT: SQLite db handle */
29577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
29583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_open_v2(
29597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *filename,   /* Database filename (UTF-8) */
29607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 **ppDb,         /* OUT: SQLite db handle */
29617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int flags,              /* Flags */
29627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zVfs        /* Name of VFS module to use */
29637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
29647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
29657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
296690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Obtain Values For URI Parameters
296790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
296890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** These are utility routines, useful to VFS implementations, that check
296990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to see if a database file was a URI that contained a specific query
297090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** parameter, and if so obtains the value of that query parameter.
297190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
297290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If F is the database filename pointer passed into the xOpen() method of
297390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a VFS implementation when the flags parameter to xOpen() has one or
297490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
297590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** P is the name of the query parameter, then
297690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_uri_parameter(F,P) returns the value of the P
297790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** parameter if it exists or a NULL pointer if P does not appear as a
297890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** query parameter on F.  If P is a query parameter of F
297990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** has no explicit value, then sqlite3_uri_parameter(F,P) returns
298090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a pointer to an empty string.
298190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
298290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
298390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** parameter and returns true (1) or false (0) according to the value
2984c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
2985c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** value of query parameter P is one of "yes", "true", or "on" in any
2986c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** case or if the value begins with a non-zero number.  The
2987c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
2988c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** query parameter P is one of "no", "false", or "off" in any case or
2989c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** if the value begins with a numeric zero.  If P is not a query
2990c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** parameter on F or if the value of P is does not match any of the
2991c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
299290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
299390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
299490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** 64-bit signed integer and returns that integer, or D if P does not
299590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** exist.  If the value of P is something other than an integer, then
299690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** zero is returned.
299790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
299890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
299990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
300090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is not a database file pathname pointer that SQLite passed into the xOpen
300190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** VFS method, then the behavior of this routine is undefined and probably
300290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** undesirable.
300390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
30043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_uri_parameter(const char *zFilename, const char *zParam);
30053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
30063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
300790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
300890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
300990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
3010a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Error Codes And Messages
3011a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
30123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the most recent sqlite3_* API call associated with
30133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [database connection] D failed, then the sqlite3_errcode(D) interface
30143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** returns the numeric [result code] or [extended result code] for that
30153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** API call.
30163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If the most recent API call was successful,
30173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** then the return value from sqlite3_errcode() is undefined.
30183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_extended_errcode()
3019a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface is the same except that it always returns the
3020a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [extended result code] even when extended result codes are
3021a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** disabled.
3022a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3023a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3024a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** text that describes the error, as either UTF-8 or UTF-16 respectively.
3025a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Memory to hold the error message string is managed internally.
3026a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The application does not need to worry about freeing the result.
30277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** However, the error string might be overwritten or deallocated by
3028a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** subsequent calls to other SQLite interface functions.)^
3029a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
30308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_errstr() interface returns the English-language text
30318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** that describes the [result code], as UTF-8.
30328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^(Memory to hold the error message string is managed internally
30338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and must not be freed by the application)^.
30348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
3035a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When the serialized [threading mode] is in use, it might be the
3036a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** case that a second error occurs on a separate thread in between
3037a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the time of the first error and the call to these interfaces.
3038a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When that happens, the second error will be reported since these
3039a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces always report the most recent result.  To avoid
3040a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this, each thread can obtain exclusive use of the [database connection] D
3041a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3042a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3043a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** all calls to the interfaces listed here are completed.
3044a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3045a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If an interface fails with SQLITE_MISUSE, that means the interface
3046a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** was invoked incorrectly by the application.  In that case, the
3047a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** error code and message may or may not be set.
30487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
30493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_errcode(sqlite3 *db);
30503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_extended_errcode(sqlite3 *db);
30513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_errmsg(sqlite3*);
30523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_errmsg16(sqlite3*);
30533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_errstr(int);
30547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
30557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3056a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: SQL Statement Object
30577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: {prepared statement} {prepared statements}
30587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** An instance of this object represents a single SQL statement.
3060a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This object is variously known as a "prepared statement" or a
30617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** "compiled SQL statement" or simply as a "statement".
3062a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
30637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The life of a statement object goes something like this:
30647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
30657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ol>
30667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> Create the object using [sqlite3_prepare_v2()] or a related
30677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**      function.
3068a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> Bind values to [host parameters] using the sqlite3_bind_*()
3069a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      interfaces.
30707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> Run the SQL by calling [sqlite3_step()] one or more times.
30717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> Reset the statement using [sqlite3_reset()] then go back
30727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**      to step 2.  Do this zero or more times.
30737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> Destroy the object using [sqlite3_finalize()].
30747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </ol>
30757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
30767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Refer to documentation on individual methods above for additional
30777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** information.
30787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
30797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_stmt sqlite3_stmt;
30807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
30817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3082a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Run-time Limits
30837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3084a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This interface allows the size of various constructs to be limited
30857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** on a connection by connection basis.  The first parameter is the
30867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [database connection] whose limit is to be set or queried.  The
30877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** second parameter is one of the [limit categories] that define a
30887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** class of constructs to be size limited.  The third parameter is the
3089de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** new limit for that construct.)^
3090a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the new limit is a negative number, the limit is unchanged.
3092de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3093a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [limits | hard upper bound]
3094de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** set at compile-time by a C preprocessor macro called
3095de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [limits | SQLITE_MAX_<i>NAME</i>].
3096a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3097a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Attempts to increase a limit above its hard upper bound are
3098a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** silently truncated to the hard upper bound.
3099a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3100de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Regardless of whether or not the limit was changed, the
3101de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_limit()] interface returns the prior value of the limit.
3102de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Hence, to find the current value of a limit without changing it,
3103de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** simply invoke this interface with the third parameter set to -1.
3104de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
3105a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Run-time limits are intended for use in applications that manage
31067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** both their own internal database and also databases that are controlled
31077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** by untrusted external sources.  An example application might be a
3108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** web browser that has its own databases for storing history and
3109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** separate databases controlled by JavaScript applications downloaded
3110a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** off the Internet.  The internal databases can be given the
31117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** large, default limits.  Databases managed by external sources can
31127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** be given much smaller limits designed to prevent a denial of service
3113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
31147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface to further control untrusted SQL.  The size of the database
31157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** created by an untrusted script can be contained using the
31167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [max_page_count] [PRAGMA].
31177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3118a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New run-time limit categories may be added in future releases.
31197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
31203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_limit(sqlite3*, int id, int newVal);
31217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
31227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3123a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Run-Time Limit Categories
3124a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {limit category} {*limit categories}
3125a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3126a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These constants define various performance limits
3127a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that can be lowered at run-time using [sqlite3_limit()].
3128a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The synopsis of the meanings of the various limits is shown below.
3129a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Additional information is available at [limits | Limits in SQLite].
31307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
31317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <dl>
313290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3133de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
31347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
313590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3136a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
31377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
313890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
31397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <dd>The maximum number of columns in a table definition or in the
3140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** result set of a [SELECT] or the maximum number of columns in an index
3141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or in an ORDER BY or GROUP BY clause.</dd>)^
31427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
314390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3144a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum depth of the parse tree on any expression.</dd>)^
31457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
314690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3147a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
31487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
314990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
31507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <dd>The maximum number of instructions in a virtual machine program
3151de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** used to implement an SQL statement.  This limit is not currently
3152de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** enforced, though that might be added in some future release of
3153de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** SQLite.</dd>)^
31547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
315590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3156a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum number of arguments on a function.</dd>)^
31577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
315890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3159a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
31607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
316190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3162a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3163a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum length of the pattern argument to the [LIKE] or
3164a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [GLOB] operators.</dd>)^
31657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
316690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3167a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3168de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3169a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
317090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3171a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>The maximum depth of recursion for triggers.</dd>)^
31723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
31733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
31743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>The maximum number of auxiliary worker threads that a single
31753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [prepared statement] may start.</dd>)^
31767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </dl>
31777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
31787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_LENGTH                    0
31797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_SQL_LENGTH                1
31807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_COLUMN                    2
31817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_EXPR_DEPTH                3
31827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_COMPOUND_SELECT           4
31837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_VDBE_OP                   5
31847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_FUNCTION_ARG              6
31857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_ATTACHED                  7
31867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
31877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_LIMIT_VARIABLE_NUMBER           9
3188a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_LIMIT_TRIGGER_DEPTH            10
31893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_LIMIT_WORKER_THREADS           11
31907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
31917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3192a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Compiling An SQL Statement
3193a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {SQL statement compiler}
31947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
31957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** To execute an SQL query, it must first be compiled into a byte-code
3196a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** program using one of these routines.
31977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3198a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The first argument, "db", is a [database connection] obtained from a
3199a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3200a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_open16()].  The database connection must not have been closed.
3201a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3202a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The second argument, "zSql", is the statement to be compiled, encoded
32037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
3204a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
3205a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** use UTF-16.
3206a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
32073fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the nByte argument is negative, then zSql is read up to the
32083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** first zero terminator. ^If nByte is positive, then it is the
32093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** number of bytes read from zSql.  ^If nByte is zero, then no prepared
32103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** statement is generated.
32113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If the caller knows that the supplied string is nul-terminated, then
32123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** there is a small performance advantage to passing an nByte parameter that
32133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is the number of bytes in the input string <i>including</i>
32143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the nul-terminator.
3215a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3216a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3217a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** past the end of the first SQL statement in zSql.  These routines only
3218a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compile the first statement in zSql, so *pzTail is left pointing to
3219a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** what remains uncompiled.
3220a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3221a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3222a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
3223a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to NULL.  ^If the input text contains no SQL (if the input is an empty
3224a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** string or a comment) then *ppStmt is set to NULL.
3225a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The calling procedure is responsible for deleting the compiled
3226a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL statement using [sqlite3_finalize()] after it has finished with it.
3227a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ppStmt may not be NULL.
3228a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3229a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3230a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** otherwise an [error code] is returned.
32317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
32327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
32337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** recommended for all new programs. The two older interfaces are retained
32347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for backwards compatibility, but their use is discouraged.
3235a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^In the "v2" interfaces, the prepared statement
3236a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that is returned (the [sqlite3_stmt] object) contains a copy of the
3237a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** original SQL text. This causes the [sqlite3_step()] interface to
3238a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** behave differently in three ways:
32397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
32407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ol>
32417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>
3242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
32437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** always used to do, [sqlite3_step()] will automatically recompile the SQL
32448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
32458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** retries will occur before sqlite3_step() gives up and returns an error.
32467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </li>
32477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
32487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>
3249a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3250a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [error codes] or [extended error codes].  ^The legacy behavior was that
3251a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3252a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the application would have to make a second call to [sqlite3_reset()]
3253a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in order to find the underlying cause of the problem. With the "v2" prepare
3254a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces, the underlying reason for the error is returned immediately.
32557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </li>
32567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3257a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li>
3258de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the specific value bound to [parameter | host parameter] in the
3259de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** WHERE clause might influence the choice of query plan for a statement,
3260de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** then the statement will be automatically recompiled, as if there had been
3261de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** a schema change, on the first  [sqlite3_step()] call following any change
3262de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** to the [sqlite3_bind_text | bindings] of that [parameter].
3263de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The specific value of WHERE-clause [parameter] might influence the
3264de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** choice of query plan if the parameter is the left-hand side of a [LIKE]
3265de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** or [GLOB] operator or if the parameter is compared to an indexed column
326690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3267a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </li>
3268a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </ol>
32697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
32703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_prepare(
32717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,            /* Database handle */
32727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zSql,       /* SQL statement, UTF-8 encoded */
32737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nByte,              /* Maximum length of zSql in bytes. */
32747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
32757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
32767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
32773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_prepare_v2(
32787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,            /* Database handle */
32797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zSql,       /* SQL statement, UTF-8 encoded */
32807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nByte,              /* Maximum length of zSql in bytes. */
32817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
32827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
32837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
32843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_prepare16(
32857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,            /* Database handle */
32867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *zSql,       /* SQL statement, UTF-16 encoded */
32877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nByte,              /* Maximum length of zSql in bytes. */
32887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
32897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
32907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
32913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_prepare16_v2(
32927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,            /* Database handle */
32937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *zSql,       /* SQL statement, UTF-16 encoded */
32947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nByte,              /* Maximum length of zSql in bytes. */
32957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
32967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
32977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
32987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
32997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3300a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Retrieving Statement SQL
33017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3302a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This interface can be used to retrieve a saved copy of the original
3303a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL text used to create a [prepared statement] if that statement was
3304a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
33057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
33063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_sql(sqlite3_stmt *pStmt);
33077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
33087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
330995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** CAPI3REF: Determine If An SQL Statement Writes The Database
331095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
331195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
331290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** and only if the [prepared statement] X makes no direct changes to
331390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the content of the database file.
331490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
331590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Note that [application-defined SQL functions] or
331690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [virtual tables] might change the database indirectly as a side effect.
331790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(For example, if an application defines a function "eval()" that
331890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** calls [sqlite3_exec()], then the following SQL statement would
331990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** change the database file through side-effects:
332090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
332190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <blockquote><pre>
332290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**    SELECT eval('DELETE FROM t1') FROM t2;
332390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </pre></blockquote>
332490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
332590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** But because the [SELECT] statement does not change the database file
332690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** directly, sqlite3_stmt_readonly() would still return true.)^
332790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
332890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
332990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
333090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** since the statements themselves do not actually modify the database but
333190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** rather they control the timing of when other statements modify the
333290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** database.  ^The [ATTACH] and [DETACH] statements also cause
333390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_stmt_readonly() to return true since, while those statements
333490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** change the configuration of a database connection, they do not make
333590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** changes to the content of the database files on disk.
333695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori*/
33373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
333895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori
333995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori/*
334090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Determine If A Prepared Statement Has Been Reset
334190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
334290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
334390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [prepared statement] S has been stepped at least once using
334490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_step(S)] but has not run to completion and/or has not
334590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
334690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** interface returns false if S is a NULL pointer.  If S is not a
334790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** NULL pointer and is not a pointer to a valid [prepared statement]
334890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** object, then the behavior is undefined and probably undesirable.
334990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
335090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** This interface can be used in combination [sqlite3_next_stmt()]
335190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to locate all prepared statements associated with a database
335290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** connection that are in need of being reset.  This can be used,
335390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** for example, in diagnostic routines to search for prepared
335490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** statements that are holding a transaction open.
335590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
33563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_stmt_busy(sqlite3_stmt*);
335790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
335890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
3359a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Dynamically Typed Value Object
33607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
33617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
33627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite uses the sqlite3_value object to represent all values
3363a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that can be stored in a database table. SQLite uses dynamic typing
3364a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for the values it stores.  ^Values stored in sqlite3_value objects
3365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be integers, floating point values, strings, BLOBs, or NULL.
33667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
33677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** An sqlite3_value object may be either "protected" or "unprotected".
33687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Some interfaces require a protected sqlite3_value.  Other interfaces
33697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** will accept either a protected or an unprotected sqlite3_value.
3370a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Every interface that accepts sqlite3_value arguments specifies
33717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** whether or not it requires a protected sqlite3_value.
33727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
33737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The terms "protected" and "unprotected" refer to whether or not
337490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a mutex is held.  An internal mutex is held for a protected
33757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_value object but no mutex is held for an unprotected
33767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_value object.  If SQLite is compiled to be single-threaded
3377a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3378a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or if SQLite is run in one of reduced mutex modes
3379a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3380a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then there is no distinction between protected and unprotected
3381a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_value objects and they can be used interchangeably.  However,
3382a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for maximum code portability it is recommended that applications
3383de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** still make the distinction between protected and unprotected
3384a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_value objects even when not strictly required.
3385a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3386a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_value objects that are passed as parameters into the
3387a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation of [application-defined SQL functions] are protected.
3388a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_value object returned by
33897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_column_value()] is unprotected.
33907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Unprotected sqlite3_value objects may only be used with
3391a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_result_value()] and [sqlite3_bind_value()].
3392a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [sqlite3_value_blob | sqlite3_value_type()] family of
3393a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces require protected sqlite3_value objects.
33947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
33957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct Mem sqlite3_value;
33967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
33977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3398a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: SQL Function Context Object
33997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
34007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The context in which an SQL function executes is stored in an
3401a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_context object.  ^A pointer to an sqlite3_context object
3402a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is always first parameter to [application-defined SQL functions].
3403a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The application-defined SQL function implementation will pass this
3404a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3405a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3406a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3407a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and/or [sqlite3_set_auxdata()].
34087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
34097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_context sqlite3_context;
34107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
34117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3412a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Binding Values To Prepared Statements
3413a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3414a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
34157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3416a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3417a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** literals may be replaced by a [parameter] that matches one of following
3418a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** templates:
34197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
34207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
34217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  ?
34227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  ?NNN
34237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  :VVV
34247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  @VVV
34257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  $VVV
34267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </ul>
34277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3428a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** In the templates above, NNN represents an integer literal,
3429de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and VVV represents an alphanumeric identifier.)^  ^The values of these
3430a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameters (also called "host parameter names" or "SQL parameters")
34317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** can be set using the sqlite3_bind_*() routines defined here.
34327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3433a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument to the sqlite3_bind_*() routines is always
3434a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a pointer to the [sqlite3_stmt] object returned from
3435a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare_v2()] or its variants.
3436a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3437a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The second argument is the index of the SQL parameter to be set.
3438a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The leftmost SQL parameter has an index of 1.  ^When the same named
3439a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL parameter is used more than once, second and subsequent
3440a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** occurrences have the same index as the first occurrence.
3441a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The index for named parameters can be looked up using the
3442a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_bind_parameter_index()] API if desired.  ^The index
34437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for "?NNN" parameters is the value of NNN.
3444a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The NNN value must be between 1 and the [sqlite3_limit()]
3445a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
34467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3447a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The third argument is the value to bind to the parameter.
34488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
34498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
34508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** is ignored and the end result is the same as sqlite3_bind_null().
34517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3452a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(In those routines that have a fourth argument, its value is the
3453a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** number of bytes in the parameter.  To be clear: the value is the
3454a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** number of <u>bytes</u> in the value, not the number of characters.)^
34558fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
34568fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** is negative, then the length of the string is
3457a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the number of bytes up to the first zero terminator.
34588fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** If the fourth parameter to sqlite3_bind_blob() is negative, then
34598fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the behavior is undefined.
346090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If a non-negative fourth parameter is provided to sqlite3_bind_text()
34613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** or sqlite3_bind_text16() or sqlite3_bind_text64() then
34623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** that parameter must be the byte offset
346390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** where the NUL terminator would occur assuming the string were NUL
346490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** terminated.  If any NUL characters occur at byte offsets less than
346590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the value of the fourth parameter then the resulting string value will
346690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** contain embedded NULs.  The result of expressions involving strings
346790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** with embedded NULs is undefined.
34687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
34693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The fifth argument to the BLOB and string binding interfaces
34703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is a destructor used to dispose of the BLOB or
347195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** string after SQLite has finished with it.  ^The destructor is called
34723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to dispose of the BLOB or string even if the call to bind API fails.
347395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^If the fifth argument is
34747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the special value [SQLITE_STATIC], then SQLite assumes that the
34757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** information is in static, unmanaged space and does not need to be freed.
3476a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
34777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLite makes its own private copy of the data immediately, before
34787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the sqlite3_bind_*() routine returns.
34797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
34803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sixth argument to sqlite3_bind_text64() must be one of
34813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
34823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to specify the encoding of the text in the third parameter.  If
34833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the sixth argument to sqlite3_bind_text64() is not one of the
34843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** allowed values shown above, or if the text encoding is different
34853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** from the encoding specified by the sixth parameter, then the behavior
34863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is undefined.
34873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
3488a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3489a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
3490a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (just an integer to hold its size) while it is being processed.
3491a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Zeroblobs are intended to serve as placeholders for BLOBs whose
3492a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** content is later written using
3493a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_blob_open | incremental BLOB I/O] routines.
3494a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A negative value for the zeroblob results in a zero-length BLOB.
3495a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3496a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3497a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for the [prepared statement] or with a prepared statement for which
3498a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3499a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
3500a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine is passed a [prepared statement] that has been finalized, the
3501a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** result is undefined and probably harmful.
3502a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3503a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3504a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Unbound parameters are interpreted as NULL.
3505a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3506a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3507a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [error code] if anything goes wrong.
35083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
35093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
35103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_MAX_LENGTH].
3511a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^[SQLITE_RANGE] is returned if the parameter
3512a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
35137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
35147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [sqlite3_bind_parameter_count()],
3515a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3516a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
35173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
35183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
35193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich                        void(*)(void*));
35203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_double(sqlite3_stmt*, int, double);
35213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_int(sqlite3_stmt*, int, int);
35223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
35233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_null(sqlite3_stmt*, int);
35243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
35253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
35263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
35273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich                         void(*)(void*), unsigned char encoding);
35283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
35293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3530a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
3531a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
3532a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Number Of SQL Parameters
35337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3534a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This routine can be used to find the number of [SQL parameters]
3535a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in a [prepared statement].  SQL parameters are tokens of the
35367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3537a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** placeholders for values that are [sqlite3_bind_blob | bound]
35387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to the parameters at a later time.
35397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3540a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This routine actually returns the index of the largest (rightmost)
3541a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter. For all forms except ?NNN, this will correspond to the
3542a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** number of unique parameters.  If parameters of the ?NNN form are used,
3543a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** there may be gaps in the list.)^
35447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
35457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [sqlite3_bind_blob|sqlite3_bind()],
35467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_name()], and
35477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_index()].
35487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
35493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_count(sqlite3_stmt*);
35507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
35517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3552a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Name Of A Host Parameter
35537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3554a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_bind_parameter_name(P,N) interface returns
3555a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the name of the N-th [SQL parameter] in the [prepared statement] P.
3556a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
35577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
35587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** respectively.
35597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** In other words, the initial ":" or "$" or "@" or "?"
3560a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is included as part of the name.)^
3561a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Parameters of the form "?" without a following integer have no name
3562a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and are referred to as "nameless" or "anonymous parameters".
35637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3564a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first host parameter has an index of 1, not 0.
35657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3566a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the value N is out of range or if the N-th parameter is
3567a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** nameless, then NULL is returned.  ^The returned string is
3568a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** always in UTF-8 encoding even if the named parameter was
35697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** originally specified as UTF-16 in [sqlite3_prepare16()] or
35707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_prepare16_v2()].
35717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
35727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [sqlite3_bind_blob|sqlite3_bind()],
35737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_count()], and
35747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_index()].
35757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
35763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_bind_parameter_name(sqlite3_stmt*, int);
35777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
35787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3579a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Index Of A Parameter With A Given Name
35807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3581a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Return the index of an SQL parameter given its name.  ^The
35827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** index value returned is suitable for use as the second
3583a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
3584a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is returned if no matching parameter is found.  ^The parameter
35857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** name must be given in UTF-8 even if the original statement
35867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
35877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
35887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [sqlite3_bind_blob|sqlite3_bind()],
35897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_count()], and
35907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_bind_parameter_index()].
35917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
35923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
35937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
35947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3595a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Reset All Bindings On A Prepared Statement
35967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3597a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
3598a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3599a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Use this routine to reset all host parameters to NULL.
36007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
36013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_clear_bindings(sqlite3_stmt*);
36027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
36037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3604a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Number Of Columns In A Result Set
36057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3606a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Return the number of columns in the result set returned by the
3607a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
3608a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** statement that does not return data (for example an [UPDATE]).
3609de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
3610de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** See also: [sqlite3_data_count()]
36117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
36123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_column_count(sqlite3_stmt *pStmt);
36137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
36147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3615a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Column Names In A Result Set
36167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3617a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines return the name assigned to a particular column
3618a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
3619a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface returns a pointer to a zero-terminated UTF-8 string
36207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and sqlite3_column_name16() returns a pointer to a zero-terminated
3621a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** UTF-16 string.  ^The first parameter is the [prepared statement]
3622a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that implements the [SELECT] statement. ^The second parameter is the
3623a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** column number.  ^The leftmost column is number 0.
36247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3625a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The returned string pointer is valid until either the [prepared statement]
362690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is destroyed by [sqlite3_finalize()] or until the statement is automatically
362790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** reprepared by the first call to [sqlite3_step()] for a particular run
362890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or until the next call to
3629a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_column_name() or sqlite3_column_name16() on the same column.
36307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3631a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_malloc() fails during the processing of either routine
36327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** (for example during a conversion from UTF-8 to UTF-16) then a
36337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** NULL pointer is returned.
36347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3635a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The name of a result column is the value of the "AS" clause for
36367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** that column, if there is an AS clause.  If there is no AS clause
36377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** then the name of the column is unspecified and may change from
36387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** one release of SQLite to the next.
36397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
36403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_column_name(sqlite3_stmt*, int N);
36413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_name16(sqlite3_stmt*, int N);
36427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
36437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3644a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Source Of Data In A Query Result
36457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3646a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines provide a means to determine the database, table, and
3647a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** table column that is the origin of a particular result column in
3648a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SELECT] statement.
3649a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The name of the database or table or column can be returned as
3650a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
36517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the database name, the _table_ routines return the table name, and
36527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the origin_ routines return the column name.
3653a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The returned string is valid until the [prepared statement] is destroyed
365490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** using [sqlite3_finalize()] or until the statement is automatically
365590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** reprepared by the first call to [sqlite3_step()] for a particular run
365690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or until the same information is requested
36577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** again in a different encoding.
36587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3659a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The names returned are the original un-aliased names of the
36607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** database, table, and column.
36617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3662a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument to these interfaces is a [prepared statement].
3663a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These functions return information about the Nth result column returned by
36647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the statement, where N is the second function argument.
3665a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The left-most column is column 0 for these routines.
36667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3667a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the Nth column returned by the statement is an expression or
3668a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** subquery and is not a column value, then all of these functions return
3669a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** NULL.  ^These routine might also return NULL if a memory allocation error
3670a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** occurs.  ^Otherwise, they return the name of the attached database, table,
3671a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or column that query result column was extracted from.
36727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3673a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^As with all other SQLite APIs, those whose names end with "16" return
3674a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** UTF-16 encoded strings and the other functions return UTF-8.
36757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3676a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These APIs are only available if the library was compiled with the
3677a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
36787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
36797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If two or more threads call one or more of these routines against the same
36807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** prepared statement and column at the same time then the results are
36817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** undefined.
36827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3683a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If two or more threads call one or more
3684a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_column_database_name | column metadata interfaces]
3685a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for the same [prepared statement] and result column
3686a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** at the same time then the results are undefined.
3687a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
36883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_column_database_name(sqlite3_stmt*,int);
36893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_database_name16(sqlite3_stmt*,int);
36903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_column_table_name(sqlite3_stmt*,int);
36913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_table_name16(sqlite3_stmt*,int);
36923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_column_origin_name(sqlite3_stmt*,int);
36933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_origin_name16(sqlite3_stmt*,int);
3694a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
3695a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
3696a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Declared Datatype Of A Query Result
3697a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3698a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The first parameter is a [prepared statement].
3699a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If this statement is a [SELECT] statement and the Nth column of the
3700a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned result set of that [SELECT] is a table column (not an
37017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** expression or subquery) then the declared type of the table
3702a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** column is returned.)^  ^If the Nth column of the result set is an
37037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** expression or subquery, then a NULL pointer is returned.
3704a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The returned string is always UTF-8 encoded.
3705a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3706a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(For example, given the database schema:
37077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
37087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** CREATE TABLE t1(c1 VARIANT);
37097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3710a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the following statement to be compiled:
37117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
37127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SELECT c1 + 1, c1 FROM t1;
37137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3714a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this routine would return the string "VARIANT" for the second result
3715a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** column (i==1), and a NULL pointer for the first result column (i==0).)^
37167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3717a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite uses dynamic run-time typing.  ^So just because a column
37187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is declared to contain a particular type does not mean that the
37197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** data stored in that column is of the declared type.  SQLite is
3720a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** strongly typed, but the typing is dynamic not static.  ^Type
37217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is associated with individual values, not with the containers
37227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** used to hold those values.
3723a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
37243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_column_decltype(sqlite3_stmt*,int);
37253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_decltype16(sqlite3_stmt*,int);
3726a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
3727a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
3728a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Evaluate An SQL Statement
3729a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3730a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** After a [prepared statement] has been prepared using either
3731a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
3732a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
3733a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must be called one or more times to evaluate the statement.
37347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3735a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The details of the behavior of the sqlite3_step() interface depend
37367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** on whether the statement was prepared using the newer "v2" interface
37377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
37387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
37397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** new "v2" interface is recommended for new applications but the legacy
37407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface will continue to be supported.
37417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3742a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
37437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
3744a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^With the "v2" interface, any of the other [result codes] or
3745a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [extended result codes] might be returned as well.
37467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3747a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
3748a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database locks it needs to do its job.  ^If the statement is a [COMMIT]
37497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or occurs outside of an explicit transaction, then you can retry the
375090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** statement.  If the statement is not a [COMMIT] and occurs within an
37517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** explicit transaction then you should rollback the transaction before
37527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** continuing.
37537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3754a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^[SQLITE_DONE] means that the statement has finished executing
37557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** successfully.  sqlite3_step() should not be called again on this virtual
37567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** machine without first calling [sqlite3_reset()] to reset the virtual
37577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** machine back to its initial state.
37587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3759a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
3760a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is returned each time a new row of data is ready for processing by the
3761a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** caller. The values may be accessed using the [column access functions].
37627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_step() is called again to retrieve the next row of data.
3763a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3764a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
37657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** violation) has occurred.  sqlite3_step() should not be called again on
37667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the VM. More information may be found by calling [sqlite3_errmsg()].
3767a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^With the legacy interface, a more specific error code (for example,
37687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
37697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** can be obtained by calling [sqlite3_reset()] on the
3770a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [prepared statement].  ^In the "v2" interface,
37717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the more specific error code is returned directly by sqlite3_step().
37727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
37737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_MISUSE] means that the this routine was called inappropriately.
37747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Perhaps it was called on a [prepared statement] that has
3775a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** already been [sqlite3_finalize | finalized] or on one that had
37767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
37777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** be the case that the same database connection is being used by two or
37787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** more threads at the same moment in time.
37797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
378090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** For all versions of SQLite up to and including 3.6.23.1, a call to
378190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_reset()] was required after sqlite3_step() returned anything
378290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** other than [SQLITE_ROW] before any subsequent invocation of
378390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_step().  Failure to reset the prepared statement using
378490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
378590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** sqlite3_step().  But after version 3.6.23.1, sqlite3_step() began
378690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** calling [sqlite3_reset()] automatically in this circumstance rather
378790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** than returning [SQLITE_MISUSE].  This is not considered a compatibility
378890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** break because any application that ever receives an SQLITE_MISUSE error
378990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
379090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** can be used to restore the legacy behavior.
379171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
3792a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
3793a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** API always returns a generic error code, [SQLITE_ERROR], following any
3794a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
3795a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
3796a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** specific [error codes] that better describes the error.
37977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** We admit that this is a goofy design.  The problem has been fixed
37987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** with the "v2" interface.  If you prepare all of your SQL statements
37997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
3800a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
3801a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the more specific [error codes] are returned directly
38027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** by sqlite3_step().  The use of the "v2" interface is recommended.
38037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
38043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_step(sqlite3_stmt*);
38057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
38067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3807a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Number of columns in a result set
38087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3809de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_data_count(P) interface returns the number of columns in the
3810de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** current row of the result set of [prepared statement] P.
3811de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If prepared statement P does not have results ready to return
3812de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
3813de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** interfaces) then sqlite3_data_count(P) returns 0.
3814de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
381590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
381690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
381790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** will return non-zero if previous call to [sqlite3_step](P) returned
381890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
381990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** where it always returns zero since each step of that multi-step
382090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** pragma returns 0 columns of data.
3821de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
3822de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** See also: [sqlite3_column_count()]
38237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
38243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_data_count(sqlite3_stmt *pStmt);
38257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
38267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3827a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Fundamental Datatypes
38287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: SQLITE_TEXT
38297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3830a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Every value in SQLite has one of five fundamental datatypes:
38317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
38327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
38337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> 64-bit signed integer
38347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> 64-bit IEEE floating point number
38357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> string
38367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> BLOB
38377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li> NULL
3838a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </ul>)^
38397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
38407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These constants are codes for each of those types.
38417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
38427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Note that the SQLITE_TEXT constant was also used in SQLite version 2
38437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for a completely different meaning.  Software that links against both
3844a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
38457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLITE_TEXT.
38467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
38477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INTEGER  1
38487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_FLOAT    2
38497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_BLOB     4
38507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_NULL     5
38517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_TEXT
38527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# undef SQLITE_TEXT
38537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#else
38547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# define SQLITE_TEXT     3
38557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
38567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE3_TEXT     3
38577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
38587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
3859a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Result Values From A Query
3860a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {column access functions}
3861a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3862a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These routines form the "result set" interface.
3863a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3864a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines return information about a single column of the current
3865a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** result row of a query.  ^In every case the first argument is a pointer
3866a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
3867a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that was returned from [sqlite3_prepare_v2()] or one of its variants)
3868a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the second argument is the index of the column for which information
3869a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** should be returned. ^The leftmost column of the result set has the index 0.
3870a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The number of columns in the result can be determined using
3871a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_column_count()].
3872a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3873a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If the SQL statement does not currently point to a valid row, or if the
3874a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** column index is out of range, the result is undefined.
38757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines may only be called when the most recent call to
38767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_step()] has returned [SQLITE_ROW] and neither
3877a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
38787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If any of these routines are called after [sqlite3_reset()] or
38797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_finalize()] or after [sqlite3_step()] has returned
38807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** something other than [SQLITE_ROW], the results are undefined.
38817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
38827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are called from a different thread while any of these routines
3883a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are pending, then the results are undefined.
38847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3885a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_column_type() routine returns the
38867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_INTEGER | datatype code] for the initial data type
3887a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
38887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
38897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** returned by sqlite3_column_type() is only meaningful if no type
38907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** conversions have occurred as described below.  After a type conversion,
38917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the value returned by sqlite3_column_type() is undefined.  Future
38927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** versions of SQLite may change the behavior of sqlite3_column_type()
38937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** following a type conversion.
38947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3895a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
38967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** routine returns the number of bytes in that BLOB or string.
3897a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
38987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the string to UTF-8 and then returns the number of bytes.
3899a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the result is a numeric value then sqlite3_column_bytes() uses
39007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
39017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the number of bytes in that string.
3902de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
3903de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
3904de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
3905de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** routine returns the number of bytes in that BLOB or string.
3906de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
3907de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the string to UTF-16 and then returns the number of bytes.
3908de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the result is a numeric value then sqlite3_column_bytes16() uses
3909de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
3910de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the number of bytes in that string.
3911de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
3912de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
3913de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The values returned by [sqlite3_column_bytes()] and
3914de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_column_bytes16()] do not include the zero terminators at the end
3915de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** of the string.  ^For clarity: the values returned by
3916de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
39177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** bytes in the string, not the number of characters.
39187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3919a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
392090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** even empty strings, are always zero-terminated.  ^The return
3921de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
39227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3923a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The object returned by [sqlite3_column_value()] is an
39247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
39257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
39267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If the [unprotected sqlite3_value] object returned by
39277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_column_value()] is used in any other way, including calls
3928a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3929a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [sqlite3_value_bytes()], then the behavior is undefined.
39307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3931a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These routines attempt to convert the value where appropriate.  ^For
39327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** example, if the internal representation is FLOAT and a text result
3933a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is requested, [sqlite3_snprintf()] is used internally to perform the
3934a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** conversion automatically.  ^(The following table details the conversions
3935a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that are applied:
39367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
39377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <blockquote>
39387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <table border="1">
39397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
39407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
39417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
39427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
39438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
39448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
39457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
39467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
3947a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
39488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
39497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
39508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
39518fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
39528fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
39537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td>  TEXT    <td>   BLOB    <td> No change
39548fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
39558fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
39567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
39577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** </table>
3958a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </blockquote>)^
39597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
39607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The table above makes reference to standard C library functions atoi()
39617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and atof().  SQLite does not really use these functions.  It has its
3962a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** own equivalent internal routines.  The atoi() and atof() names are
39637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** used in the table for brevity and because they are familiar to most
39647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** C programmers.
39657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3966de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Note that when type conversions occur, pointers returned by prior
39677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
3968a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_column_text16() may be invalidated.
3969de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Type conversions and pointer invalidations might occur
39707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in the following cases:
39717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
39727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
3973a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> The initial content is a BLOB and sqlite3_column_text() or
3974a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      sqlite3_column_text16() is called.  A zero-terminator might
3975a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      need to be added to the string.</li>
3976a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3977a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      sqlite3_column_text16() is called.  The content must be converted
3978a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      to UTF-16.</li>
3979a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3980a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      sqlite3_column_text() is called.  The content must be converted
3981a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**      to UTF-8.</li>
3982de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ul>
3983a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
3984a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Conversions between UTF-16be and UTF-16le are always done in place and do
39857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** not invalidate a prior pointer, though of course the content of the buffer
3986de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** that the prior pointer references will have been modified.  Other kinds
3987a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of conversion are done in place when it is possible, but sometimes they
3988a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are not possible and in those cases prior pointers are invalidated.
39897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3990de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The safest and easiest to remember policy is to invoke these routines
39917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in one of the following ways:
39927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3993a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <ul>
39947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
39957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
39967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
3997de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ul>
39987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
3999a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** In other words, you should call sqlite3_column_text(),
4000a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4001a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** into the desired format, then invoke sqlite3_column_bytes() or
4002a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
4003a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4004a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4005a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with calls to sqlite3_column_bytes().
40067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4007a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The pointers returned are valid until a type conversion occurs as
40087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4009a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
4010a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
40118fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
40127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_free()].
40137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4014a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If a memory allocation error occurs during the evaluation of any
40157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of these routines, a default value is returned.  The default value
40167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is either the integer 0, the floating point number 0.0, or a NULL
40177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** pointer.  Subsequent calls to [sqlite3_errcode()] will return
4018a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_NOMEM].)^
4019a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
40203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_blob(sqlite3_stmt*, int iCol);
40213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_column_bytes(sqlite3_stmt*, int iCol);
40223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
40233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API double SQLITE_STDCALL sqlite3_column_double(sqlite3_stmt*, int iCol);
40243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_column_int(sqlite3_stmt*, int iCol);
40253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_column_int64(sqlite3_stmt*, int iCol);
40263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_column_text(sqlite3_stmt*, int iCol);
40273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_column_text16(sqlite3_stmt*, int iCol);
40283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_column_type(sqlite3_stmt*, int iCol);
40293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_value *SQLITE_STDCALL sqlite3_column_value(sqlite3_stmt*, int iCol);
4030a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
4031a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
4032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Destroy A Prepared Statement Object
40337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_finalize() function is called to delete a [prepared statement].
403590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^If the most recent evaluation of the statement encountered no errors
403695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** or if the statement is never been evaluated, then sqlite3_finalize() returns
403795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
403895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** sqlite3_finalize(S) returns the appropriate [error code] or
403995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** [extended error code].
404095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
404195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The sqlite3_finalize(S) routine can be called at any point during
404295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** the life cycle of [prepared statement] S:
404395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** before statement S is ever evaluated, after
404495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** one or more calls to [sqlite3_reset()], or after any call
404595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** to [sqlite3_step()] regardless of whether or not the statement has
404695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** completed execution.
404795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
404895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
404995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
405095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** The application must finalize every [prepared statement] in order to avoid
405195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** resource leaks.  It is a grievous error for the application to try to use
405295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** a prepared statement after it has been finalized.  Any use of a prepared
405395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** statement after it has been finalized can result in undefined and
405495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** undesirable behavior such as segfaults and heap corruption.
40557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
40563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_finalize(sqlite3_stmt *pStmt);
40577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
40587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Reset A Prepared Statement Object
40607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4061a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_reset() function is called to reset a [prepared statement]
4062a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** object back to its initial state, ready to be re-executed.
4063a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Any SQL statement variables that had values bound to them using
40647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
40657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Use [sqlite3_clear_bindings()] to reset the bindings.
40667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4067a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
4068a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** back to the beginning of its program.
40697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4070a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the most recent call to [sqlite3_step(S)] for the
4071a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
4072a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or if [sqlite3_step(S)] has never before been called on S,
4073a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then [sqlite3_reset(S)] returns [SQLITE_OK].
40747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4075a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the most recent call to [sqlite3_step(S)] for the
4076a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [prepared statement] S indicated an error, then
4077a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_reset(S)] returns an appropriate [error code].
40787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4079a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_reset(S)] interface does not change the values
4080a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
40817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
40823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_reset(sqlite3_stmt *pStmt);
40837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
40847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4085a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Create Or Redefine SQL Functions
4086a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {function creation routines}
4087a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {application-defined SQL function}
4088a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {application-defined SQL functions}
4089a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4090de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^These functions (collectively known as "function creation routines")
4091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** are used to add SQL functions or aggregates or to redefine the behavior
4092de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** of existing SQL functions or aggregates.  The only differences between
4093de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** these routines are the text encoding expected for
409490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the second parameter (the name of the function being created)
4095de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and the presence or absence of a destructor callback for
4096de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the application data pointer.
4097a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4098a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first parameter is the [database connection] to which the SQL
4099a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function is to be added.  ^If an application uses more than one database
4100a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection then application-defined SQL functions must be added
4101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to each database connection separately.
4102a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4103de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The second parameter is the name of the SQL function to be created or
4104de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
4105de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** representation, exclusive of the zero-terminator.  ^Note that the name
4106de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
4107de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Any attempt to create a function with a longer name
4108de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** will result in [SQLITE_MISUSE] being returned.
4109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4110a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The third parameter (nArg)
4111a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is the number of arguments that the SQL function or
4112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** aggregate takes. ^If this parameter is -1, then the SQL function or
4113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** aggregate may take any number of arguments between 0 and the limit
4114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
4115a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter is less than -1 or greater than 127 then the behavior is
4116a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** undefined.
41177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4118de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The fourth parameter, eTextRep, specifies what
41197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_UTF8 | text encoding] this SQL function prefers for
41208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** its parameters.  The application should set this parameter to
41218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_UTF16LE] if the function implementation invokes
41228fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
41238fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** implementation invokes [sqlite3_value_text16be()] on an input, or
41248fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
41258fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** otherwise.  ^The same SQL function may be registered multiple times using
41268fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** different preferred text encodings, with different implementations for
41278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** each encoding.
4128a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When multiple implementations of the same function are available, SQLite
41297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** will pick the one that involves the least amount of data conversion.
41308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
41318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
41328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to signal that the function will always return the same result given
41338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the same inputs within a single SQL statement.  Most SQL functions are
41348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** deterministic.  The built-in [random()] SQL function is an example of a
41358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** function that is not deterministic.  The SQLite query planner is able to
41368fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** perform additional optimizations on deterministic functions, so use
41378fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
41387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4139a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
4140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function can gain access to this pointer using [sqlite3_user_data()].)^
41417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
414290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
4143a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pointers to C-language functions that implement the SQL function or
4144a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** aggregate. ^A scalar SQL function requires an implementation of the xFunc
4145de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** callback only; NULL pointers must be passed as the xStep and xFinal
4146a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameters. ^An aggregate SQL function requires an implementation of xStep
4147de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
414890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** SQL function or aggregate, pass NULL pointers for all three function
4149de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** callbacks.
4150de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
415190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
415295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** then it is destructor for the application data pointer.
415395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** The destructor is invoked when the function is deleted, either by being
415495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** overloaded or when the database connection closes.)^
415595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The destructor is also invoked if the call to
415695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** sqlite3_create_function_v2() fails.
415795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^When the destructor callback of the tenth parameter is invoked, it
415895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** is passed a single argument which is a copy of the application data
415995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** pointer which was the fifth parameter to sqlite3_create_function_v2().
4160a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4161a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^It is permitted to register multiple implementations of the same
41627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** functions with the same name but with either differing numbers of
4163a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** arguments or differing preferred text encodings.  ^SQLite will use
4164a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the implementation that most closely matches the way in which the
4165a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQL function is used.  ^A function implementation with a non-negative
4166a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** nArg parameter is a better match than a function implementation with
4167a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a negative nArg.  ^A function where the preferred text encoding
4168a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** matches the database encoding is a better
4169a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** match than a function where the encoding is different.
4170a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A function where the encoding difference is between UTF16le and UTF16be
4171a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is a closer match than a function where the encoding difference is
4172a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** between UTF8 and UTF16.
4173a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4174a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Built-in functions may be overloaded by new application-defined functions.
4175a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4176a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^An application-defined function is permitted to call other
4177a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite interfaces.  However, such calls must not
4178a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** close the database connection nor finalize or reset the prepared
4179a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** statement in which the function is running.
4180a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
41813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_function(
41827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,
41837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zFunctionName,
41847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nArg,
41857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int eTextRep,
41867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *pApp,
41877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
41887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
41897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xFinal)(sqlite3_context*)
41907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
41913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_function16(
41927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,
41937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *zFunctionName,
41947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nArg,
41957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int eTextRep,
41967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void *pApp,
41977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
41987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
41997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void (*xFinal)(sqlite3_context*)
42007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
42013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_function_v2(
4202de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  sqlite3 *db,
4203de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  const char *zFunctionName,
4204de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  int nArg,
4205de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  int eTextRep,
4206de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pApp,
4207de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4208de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4209de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void (*xFinal)(sqlite3_context*),
4210de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void(*xDestroy)(void*)
4211de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori);
42127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
42137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4214a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Text Encodings
42157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
42167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These constant define integer codes that represent the various
42177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** text encodings supported by SQLite.
42187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
42193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
42203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
42213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
42227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_UTF16          4    /* Use native byte order */
42238fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_ANY            5    /* Deprecated */
42247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
42257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
42267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
42278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** CAPI3REF: Function Flags
42288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
42298fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** These constants may be ORed together with the
42308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
42318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to [sqlite3_create_function()], [sqlite3_create_function16()], or
42328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_create_function_v2()].
42338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich*/
42348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_DETERMINISTIC    0x800
42358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich
42368fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich/*
4237a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Deprecated Functions
4238a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** DEPRECATED
42397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4240a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These functions are [deprecated].  In order to maintain
4241a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** backwards compatibility with older code, these functions continue
4242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to be supported.  However, new applications should avoid
42433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the use of these functions.  To encourage programmers to avoid
42443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** these functions, we will not explain what they do.
42457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
4246a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#ifndef SQLITE_OMIT_DEPRECATED
42473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_aggregate_count(sqlite3_context*);
42483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_expired(sqlite3_stmt*);
42493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
42503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_global_recover(void);
42513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_thread_cleanup(void);
42523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
42538fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich                      void*,sqlite3_int64);
4254a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#endif
42557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
42567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4257a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Obtaining SQL Function Parameter Values
42587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
42597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The C-language implementation of SQL functions and aggregates uses
42607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** this set of interface routines to access the parameter values on
42617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the function or aggregate.
42627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
42637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The xFunc (for scalar functions) or xStep (for aggregates) parameters
42647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to [sqlite3_create_function()] and [sqlite3_create_function16()]
42657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** define callbacks that implement the SQL functions and aggregates.
426690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The 3rd parameter to these callbacks is an array of pointers to
42677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
42687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** each parameter to the SQL function.  These routines are used to
42697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** extract values from the [sqlite3_value] objects.
42707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
42717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines work only with [protected sqlite3_value] objects.
42727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Any attempt to use these routines on an [unprotected sqlite3_value]
42737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** object results in undefined behavior.
42747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4275a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines work just like the corresponding [column access functions]
42763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** except that these routines take a single [protected sqlite3_value] object
4277a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
42787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4279a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4280a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in the native byte-order of the host machine.  ^The
42817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4282a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** extract UTF-16 strings as big-endian and little-endian respectively.
42837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4284a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The sqlite3_value_numeric_type() interface attempts to apply
42857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** numeric affinity to the value.  This means that an attempt is
42867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** made to convert the value to an integer or floating point.  If
42877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** such a conversion is possible without loss of information (in other
4288a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** words, if the value is a string that looks like a number)
4289a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the conversion is performed.  Otherwise no conversion occurs.
4290a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
42917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4292a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Please pay particular attention to the fact that the pointer returned
4293a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from [sqlite3_value_blob()], [sqlite3_value_text()], or
42947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_value_text16()] can be invalidated by a subsequent call to
42957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4296a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [sqlite3_value_text16()].
42977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
42987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines must be called from the same thread as
42997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the SQL function that supplied the [sqlite3_value*] parameters.
4300a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
43013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_value_blob(sqlite3_value*);
43023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_value_bytes(sqlite3_value*);
43033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_value_bytes16(sqlite3_value*);
43043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API double SQLITE_STDCALL sqlite3_value_double(sqlite3_value*);
43053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_value_int(sqlite3_value*);
43063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_value_int64(sqlite3_value*);
43073fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_value_text(sqlite3_value*);
43083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16(sqlite3_value*);
43093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16le(sqlite3_value*);
43103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16be(sqlite3_value*);
43113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_value_type(sqlite3_value*);
43123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_value_numeric_type(sqlite3_value*);
4313a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
4314a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
4315a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Obtain Aggregate Function Context
4316a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4317de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Implementations of aggregate SQL functions use this
4318a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine to allocate memory for storing their state.
4319a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4320a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first time the sqlite3_aggregate_context(C,N) routine is called
4321a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for a particular aggregate function, SQLite
4322a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocates N of memory, zeroes out that memory, and returns a pointer
4323a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the new memory. ^On second and subsequent calls to
4324a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_aggregate_context() for the same aggregate function instance,
4325a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the same buffer is returned.  Sqlite3_aggregate_context() is normally
4326a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** called once for each invocation of the xStep callback and then one
4327a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** last time when the xFinal callback is invoked.  ^(When no rows match
4328a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an aggregate query, the xStep() callback of the aggregate function
4329a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation is never called and xFinal() is called exactly once.
4330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** In those cases, sqlite3_aggregate_context() might be called for the
4331a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** first time from within xFinal().)^
4332a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
43338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
43348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** when first called if N is less than or equal to zero or if a memory
43358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** allocate error occurs.
4336a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4337a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4338a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** determined by the N parameter on first successful call.  Changing the
4339a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value of N in subsequent call to sqlite3_aggregate_context() within
4340a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the same aggregate function instance will not resize the memory
43418fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** allocation.)^  Within the xFinal callback, it is customary to set
43428fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
43438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** pointless memory allocations occur.
4344a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4345a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite automatically frees the memory allocated by
4346a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_aggregate_context() when the aggregate query concludes.
4347a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4348a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The first parameter must be a copy of the
4349a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_context | SQL function context] that is the first parameter
4350a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the xStep or xFinal callback routine that implements the aggregate
43517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** function.
43527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
43537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This routine must be called from the same thread in which
43547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the aggregate SQL function is running.
43557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
43563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_aggregate_context(sqlite3_context*, int nBytes);
43577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
43587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4359a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: User Data For Functions
43607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4361a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_user_data() interface returns a copy of
43627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the pointer that was the pUserData parameter (the 5th parameter)
4363a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the [sqlite3_create_function()]
43647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and [sqlite3_create_function16()] routines that originally
4365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** registered the application defined function.
43667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
43677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This routine must be called from the same thread in which
43687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the application-defined function is running.
43697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
43703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_user_data(sqlite3_context*);
43717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
43727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4373a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Database Connection For Functions
43747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4375a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_context_db_handle() interface returns a copy of
43767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the pointer to the [database connection] (the 1st parameter)
4377a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the [sqlite3_create_function()]
43787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and [sqlite3_create_function16()] routines that originally
43797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** registered the application defined function.
43807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
43813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_context_db_handle(sqlite3_context*);
43827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
43837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4384a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Function Auxiliary Data
43857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
43868fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** These functions may be used by (non-aggregate) SQL functions to
4387a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** associate metadata with argument values. If the same value is passed to
43887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** multiple invocations of the same SQL function during query execution, under
43898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** some circumstances the associated metadata may be preserved.  An example
43908fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** of where this might be useful is in a regular-expression matching
43918fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** function. The compiled version of the regular expression can be stored as
43928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** metadata associated with the pattern string.
43938fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Then as long as the pattern string remains the same,
43948fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the compiled regular expression can be reused on multiple
43958fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** invocations of the same function.
43967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4397a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
43987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** associated by the sqlite3_set_auxdata() function with the Nth argument
43998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** value to the application-defined function. ^If there is no metadata
44008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** associated with the function argument, this sqlite3_get_auxdata() interface
44018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** returns a NULL pointer.
44028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
44038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
44048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** argument of the application-defined function.  ^Subsequent
44058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** calls to sqlite3_get_auxdata(C,N) return P from the most recent
44068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
44078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** NULL if the metadata has been discarded.
44088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
44098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQLite will invoke the destructor function X with parameter P exactly
44108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** once, when the metadata is discarded.
44118fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQLite is free to discard the metadata at any time, including: <ul>
44128fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li> when the corresponding function parameter changes, or
44138fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
44148fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**      SQL statement, or
44158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
44168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <li> during the original sqlite3_set_auxdata() call when a memory
44178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**      allocation error occurs. </ul>)^
44188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
44198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Note the last bullet in particular.  The destructor X in
44208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
44218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
44228fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** should be called near the end of the function implementation and the
44238fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** function implementation should not make any use of P after
44248fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_set_auxdata() has been called.
44257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4426a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(In practice, metadata is preserved between function calls for
44278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** function parameters that are compile-time constants, including literal
44288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** values and [parameters] and expressions composed from the same.)^
44297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
44307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines must be called from the same thread in which
44317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the SQL function is running.
44327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
44333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_get_auxdata(sqlite3_context*, int N);
44343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
44357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
44367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
44377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4438a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Constants Defining Special Destructor Behavior
44397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4440a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These are special values for the destructor that is passed in as the
4441a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
44427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** argument is SQLITE_STATIC, it means that the content pointer is constant
4443a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and will never change.  It does not need to be destroyed.  ^The
44447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLITE_TRANSIENT value means that the content will likely change in
44457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the near future and that SQLite should make its own private copy of
44467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the content before returning.
44477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
44487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The typedef is necessary to work around problems in certain
44498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** C++ compilers.
44507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
44517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef void (*sqlite3_destructor_type)(void*);
44527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
44537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
44547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
44557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4456a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Setting The Result Of An SQL Function
44577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
44587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These routines are used by the xFunc or xFinal callbacks that
44597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** implement SQL functions and aggregates.  See
44607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_create_function()] and [sqlite3_create_function16()]
44617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for additional information.
44627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4463a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These functions work very much like the [parameter binding] family of
4464a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** functions used to bind values to host parameters in prepared statements.
4465a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Refer to the [SQL parameter] documentation for additional information.
44667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4467a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_blob() interface sets the result from
4468a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an application-defined function to be the BLOB whose content is pointed
44697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to by the second parameter and which is N bytes long where N is the
4470a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** third parameter.
4471a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4472a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_zeroblob() interfaces set the result of
4473a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the application-defined function to be a BLOB containing all zero
44747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** bytes and N bytes in size, where N is the value of the 2nd parameter.
44757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4476a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_double() interface sets the result from
4477a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an application-defined function to be a floating point value specified
44787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** by its 2nd argument.
44797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4480a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_error() and sqlite3_result_error16() functions
44817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** cause the implemented SQL function to throw an exception.
4482a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite uses the string pointed to by the
44837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4484a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** as the text of an error message.  ^SQLite interprets the error
4485a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** message string from sqlite3_result_error() as UTF-8. ^SQLite
4486a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interprets the string from sqlite3_result_error16() as UTF-16 in native
4487a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** byte order.  ^If the third parameter to sqlite3_result_error()
44887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or sqlite3_result_error16() is negative then SQLite takes as the error
44897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** message all text up through the first zero character.
4490a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the third parameter to sqlite3_result_error() or
44917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_result_error16() is non-negative then SQLite takes that many
44927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** bytes (not characters) from the 2nd parameter as the error message.
4493a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_error() and sqlite3_result_error16()
4494a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines make a private copy of the error message text before
44957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** they return.  Hence, the calling function can deallocate or
44967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** modify the text after they return without harm.
4497a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_error_code() function changes the error code
4498a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned by SQLite as a result of an error in a function.  ^By default,
4499a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
45007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
45017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
45028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
45038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** error indicating that a string or BLOB is too long to represent.
4504a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
45058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
45068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** error indicating that a memory allocation failed.
45077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4508a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_int() interface sets the return value
45097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the application-defined function to be the 32-bit signed integer
45107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** value given in the 2nd argument.
4511a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_int64() interface sets the return value
45127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the application-defined function to be the 64-bit signed integer
45137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** value given in the 2nd argument.
45147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4515a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_null() interface sets the return value
45167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the application-defined function to be NULL.
45177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4518a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_text(), sqlite3_result_text16(),
45197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
45207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** set the return value of the application-defined function to be
45217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** a text string which is represented as UTF-8, UTF-16 native byte order,
45227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** UTF-16 little endian, or UTF-16 big endian, respectively.
45233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_result_text64() interface sets the return value of an
45243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** application-defined function to be a text string in an encoding
45253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** specified by the fifth (and last) parameter, which must be one
45263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
4527a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite takes the text result from the application from
45287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the 2nd parameter of the sqlite3_result_text* interfaces.
4529a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4530a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is negative, then SQLite takes result text from the 2nd parameter
45317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** through the first zero character.
4532a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 3rd parameter to the sqlite3_result_text* interfaces
45337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is non-negative, then as many bytes (not characters) of the text
45347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** pointed to by the 2nd parameter are taken as the application-defined
453590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** function result.  If the 3rd parameter is non-negative, then it
453690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** must be the byte offset into the string where the NUL terminator would
453790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** appear if the string where NUL terminated.  If any NUL characters occur
453890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** in the string at a byte offset that is less than the value of the 3rd
453990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** parameter, then the resulting string will contain embedded NULs and the
454090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** result of expressions operating on strings with embedded NULs is undefined.
4541a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 4th parameter to the sqlite3_result_text* interfaces
45427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4543a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function as the destructor on the text or BLOB result when it has
45447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** finished using that result.
4545a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
4546a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4547a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** assumes that the text or BLOB result is in constant space and does not
4548a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** copy the content of the parameter nor call a destructor on the content
4549a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when it has finished using that result.
4550a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the 4th parameter to the sqlite3_result_text* interfaces
45517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
45527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** then SQLite makes a copy of the result into space obtained from
45537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** from [sqlite3_malloc()] before it returns.
45547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4555a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_result_value() interface sets the result of
45567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the application-defined function to be a copy the
4557a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
45587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4559a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** so that the [sqlite3_value] specified in the parameter may change or
45607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** be deallocated after sqlite3_result_value() returns without harm.
4561a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A [protected sqlite3_value] object may always be used where an
45627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [unprotected sqlite3_value] object is required, so either
45637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** kind of [sqlite3_value] object can be used with this interface.
45647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4565a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If these routines are called from within the different thread
4566a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** than the one containing the application-defined function that received
45677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the [sqlite3_context] pointer, the results are undefined.
4568a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
45693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
45703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_blob64(sqlite3_context*,const void*,
45713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich                           sqlite3_uint64,void(*)(void*));
45723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_double(sqlite3_context*, double);
45733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_error(sqlite3_context*, const char*, int);
45743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_error16(sqlite3_context*, const void*, int);
45753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_error_toobig(sqlite3_context*);
45763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_error_nomem(sqlite3_context*);
45773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_error_code(sqlite3_context*, int);
45783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_int(sqlite3_context*, int);
45793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
45803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_null(sqlite3_context*);
45813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
45823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
45833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich                           void(*)(void*), unsigned char encoding);
45843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
45853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
45863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
45873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_value(sqlite3_context*, sqlite3_value*);
45883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_result_zeroblob(sqlite3_context*, int n);
4589a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
4590a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
4591a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Define New Collating Sequences
45927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4593de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^These functions add, remove, or modify a [collation] associated
4594de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** with the [database connection] specified as the first argument.
45957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4596de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The name of the collation is a UTF-8 string
45977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4598de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and a UTF-16 string in native byte order for sqlite3_create_collation16().
4599de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
4600de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** considered to be the same name.
4601de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
4602de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(The third argument (eTextRep) must be one of the constants:
4603de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <ul>
4604de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> [SQLITE_UTF8],
4605de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> [SQLITE_UTF16LE],
4606de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> [SQLITE_UTF16BE],
4607de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> [SQLITE_UTF16], or
4608de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> [SQLITE_UTF16_ALIGNED].
4609de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ul>)^
4610de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The eTextRep argument determines the encoding of strings passed
4611de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** to the collating function callback, xCallback.
4612de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
4613de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** force strings to be UTF16 with native byte order.
4614de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
4615de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** on an even byte address.
4616de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
461790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The fourth argument, pArg, is an application data pointer that is passed
4618de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** through as the first argument to the collating function callback.
4619de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
4620de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The fifth argument, xCallback, is a pointer to the collating function.
4621de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Multiple collating functions can be registered using the same name but
4622de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** with different eTextRep parameters and SQLite will use whichever
4623de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** function requires the least amount of data transformation.
4624de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the xCallback argument is NULL then the collating function is
4625de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** deleted.  ^When all collating functions having the same name are deleted,
4626de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** that collation is no longer usable.
4627de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
4628de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The collating function callback is invoked with a copy of the pArg
4629de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** application data pointer and with two strings in the encoding specified
4630de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** by the eTextRep argument.  The collating function must return an
4631de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** integer that is negative, zero, or positive
4632de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** if the first string is less than, equal to, or greater than the second,
463390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** respectively.  A collating function must always return the same answer
4634de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** given the same inputs.  If two or more collating functions are registered
4635de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** to the same collation name (using different eTextRep values) then all
4636de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** must give an equivalent answer when invoked with equivalent strings.
4637de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The collating function must obey the following properties for all
4638de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** strings A, B, and C:
4639de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
4640de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <ol>
4641de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> If A==B then B==A.
4642de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> If A==B and B==C then A==C.
4643de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> If A&lt;B THEN B&gt;A.
4644de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> If A&lt;B and B&lt;C then A&lt;C.
4645de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ol>
4646de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
4647de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** If a collating function fails any of the above constraints and that
4648de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** collating function is  registered and used, then the behavior of SQLite
4649de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** is undefined.
4650a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4651a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
4652de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** with the addition that the xDestroy callback is invoked on pArg when
4653de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the collating function is deleted.
4654de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Collating functions are deleted when they are overridden by later
4655de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** calls to the collation creation functions or when the
4656de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [database connection] is closed using [sqlite3_close()].
46577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
465895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The xDestroy callback is <u>not</u> called if the
465995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** sqlite3_create_collation_v2() function fails.  Applications that invoke
466095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
466195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** check the return code and dispose of the application data pointer
466295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** themselves rather than expecting SQLite to deal with it for them.
466395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** This is different from every other SQLite interface.  The inconsistency
466495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** is unfortunate but cannot be changed without breaking backwards
466595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** compatibility.
466695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
4667a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
46687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
46693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_collation(
46707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
46717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zName,
46727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int eTextRep,
4673de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pArg,
46747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int(*xCompare)(void*,int,const void*,int,const void*)
46757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
46763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_collation_v2(
46777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
46787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zName,
46797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int eTextRep,
4680de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pArg,
46817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int(*xCompare)(void*,int,const void*,int,const void*),
46827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void(*xDestroy)(void*)
46837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
46843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_collation16(
46857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
4686a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const void *zName,
46877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int eTextRep,
4688de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pArg,
46897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int(*xCompare)(void*,int,const void*,int,const void*)
46907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
46917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
46927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4693a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Collation Needed Callbacks
46947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4695a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^To avoid having to register all collation sequences before a database
46967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** can be used, a single callback function may be registered with the
4697a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection] to be invoked whenever an undefined collation
4698a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sequence is required.
46997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4700a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the function is registered using the sqlite3_collation_needed() API,
47017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** then it is passed the names of undefined collation sequences as strings
4702a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
4703a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the names are passed as UTF-16 in machine native byte order.
4704a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A call to either function replaces the existing collation-needed callback.
47057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4706a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(When the callback is invoked, the first argument passed is a copy
47077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the second argument to sqlite3_collation_needed() or
47087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_collation_needed16().  The second argument is the database
4709a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
4710a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
4711a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sequence function required.  The fourth parameter is the name of the
4712a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** required collation sequence.)^
47137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
47147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The callback function should register the desired collation using
47157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
47167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_create_collation_v2()].
47177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
47183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_collation_needed(
47197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
47207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void*,
47217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void(*)(void*,sqlite3*,int eTextRep,const char*)
47227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
47233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_collation_needed16(
47247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
47257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void*,
47267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void(*)(void*,sqlite3*,int eTextRep,const void*)
47277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
47287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
472971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#ifdef SQLITE_HAS_CODEC
47307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
47317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Specify the key for an encrypted database.  This routine should be
47327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** called right after sqlite3_open().
47337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
47347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The code to implement this API is not available in the public release
47357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of SQLite.
47367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
47373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_key(
47387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,                   /* Database to be rekeyed */
47397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *pKey, int nKey     /* The key */
47407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
47413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_key_v2(
47428fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  sqlite3 *db,                   /* Database to be rekeyed */
47438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  const char *zDbName,           /* Name of the database */
47448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  const void *pKey, int nKey     /* The key */
47458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich);
47467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
47477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
47487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Change the key on an open database.  If the current database is not
47497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
47507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** database is decrypted.
47517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
47527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The code to implement this API is not available in the public release
47537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of SQLite.
47547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
47553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_rekey(
47567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,                   /* Database to be rekeyed */
47577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const void *pKey, int nKey     /* The new key */
47587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
47593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_rekey_v2(
47608fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  sqlite3 *db,                   /* Database to be rekeyed */
47618fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  const char *zDbName,           /* Name of the database */
47628fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  const void *pKey, int nKey     /* The new key */
47638fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich);
47647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
47657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
476671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** Specify the activation key for a SEE database.  Unless
476771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** activated, none of the SEE routines will work.
476871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
47693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_activate_see(
477071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  const char *zPassPhrase        /* Activation phrase */
477171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori);
477271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#endif
477371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
477471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#ifdef SQLITE_ENABLE_CEROD
477571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
477671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** Specify the activation key for a CEROD database.  Unless
477771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** activated, none of the CEROD routines will work.
477871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
47793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_activate_cerod(
478071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  const char *zPassPhrase        /* Activation phrase */
478171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori);
478271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#endif
478371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
478471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
4785a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Suspend Execution For A Short Time
47867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4787de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The sqlite3_sleep() function causes the current thread to suspend execution
47887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for at least a number of milliseconds specified in its parameter.
47897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4790de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** If the operating system does not support sleep requests with
4791a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** millisecond time resolution, then the time will be rounded up to
4792de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the nearest second. The number of milliseconds of sleep actually
47937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** requested from the operating system is returned.
47947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4795a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite implements this interface by calling the xSleep()
4796de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** method of the default [sqlite3_vfs] object.  If the xSleep() method
4797de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** of the default VFS is not implemented correctly, or not implemented at
4798de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** all, then the behavior of sqlite3_sleep() may deviate from the description
4799de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** in the previous paragraphs.
48007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
48013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_sleep(int);
48027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
48037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4804a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Name Of The Folder Holding Temporary Files
4805a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4806a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If this global variable is made to point to a string which is
4807a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the name of a folder (a.k.a. directory), then all temporary files
4808a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** created by SQLite when using a built-in [sqlite3_vfs | VFS]
4809a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will be placed in that directory.)^  ^If this variable
4810a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is a NULL pointer, then SQLite performs a search for an appropriate
4811a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** temporary file directory.
4812a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
48139bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** Applications are strongly discouraged from using this global variable.
48149bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** It is required to set a temporary folder on Windows Runtime (WinRT).
48159bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** But for all other platforms, it is highly recommended that applications
48169bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** neither read nor write this variable.  This global variable is a relic
48179bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** that exists for backwards compatibility of legacy applications and should
48189bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** be avoided in new projects.
48199bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown**
4820a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** It is not safe to read or modify this variable in more than one
4821a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** thread at a time.  It is not safe to read or modify this variable
4822a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if a [database connection] is being used at the same time in a separate
4823a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** thread.
4824a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** It is intended that this variable be set once
48257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** as part of process initialization and before any SQLite interface
4826a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines have been called and that this variable remain unchanged
4827a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** thereafter.
4828a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4829a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [temp_store_directory pragma] may modify this variable and cause
4830a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
4831a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [temp_store_directory pragma] always assumes that any string
4832a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that this variable points to is held in memory obtained from
4833a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_malloc] and the pragma may attempt to free that memory
4834a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** using [sqlite3_free].
4835a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Hence, if this variable is modified directly, either it should be
4836a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** made NULL or made to point to memory obtained from [sqlite3_malloc]
4837a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or else the use of the [temp_store_directory pragma] should be avoided.
48389bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** Except when requested by the [temp_store_directory pragma], SQLite
48399bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** does not free the memory that sqlite3_temp_directory points to.  If
48409bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** the application wants that memory to be freed, it must do
48419bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** so itself, taking care to only do so after all [database connection]
48429bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** objects have been destroyed.
48438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
48458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
48468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** features that require the use of temporary files may fail.  Here is an
48478fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** example of how to do this using C++ with the Windows Runtime:
48488fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48498fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <blockquote><pre>
48508fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
48518fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** &nbsp;     TemporaryFolder->Path->Data();
48528fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** char zPathBuf&#91;MAX_PATH + 1&#93;;
48538fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** memset(zPathBuf, 0, sizeof(zPathBuf));
48548fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
48558fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** &nbsp;     NULL, NULL);
48568fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
48578fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** </pre></blockquote>
48587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
4859a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu NoriSQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
48607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
48617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
48628fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** CAPI3REF: Name Of The Folder Holding Database Files
48638fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48648fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^(If this global variable is made to point to a string which is
48658fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the name of a folder (a.k.a. directory), then all database files
48668fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** specified with a relative pathname and created or accessed by
48678fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
48688fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to be relative to that directory.)^ ^If this variable is a NULL
48698fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** pointer, then SQLite assumes that all database files specified
48708fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** with a relative pathname are relative to the current directory
48718fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** for the process.  Only the windows VFS makes use of this global
48728fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** variable; it is ignored by the unix VFS.
48738fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48748fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Changing the value of this variable while a database connection is
48758fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** open can result in a corrupt database.
48768fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** It is not safe to read or modify this variable in more than one
48788fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** thread at a time.  It is not safe to read or modify this variable
48798fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** if a [database connection] is being used at the same time in a separate
48808fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** thread.
48818fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** It is intended that this variable be set once
48828fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** as part of process initialization and before any SQLite interface
48838fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** routines have been called and that this variable remain unchanged
48848fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** thereafter.
48858fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
48868fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The [data_store_directory pragma] may modify this variable and cause
48878fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
48888fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the [data_store_directory pragma] always assumes that any string
48898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** that this variable points to is held in memory obtained from
48908fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_malloc] and the pragma may attempt to free that memory
48918fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** using [sqlite3_free].
48928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Hence, if this variable is modified directly, either it should be
48938fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** made NULL or made to point to memory obtained from [sqlite3_malloc]
48948fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** or else the use of the [data_store_directory pragma] should be avoided.
48958fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich*/
48968fecf56c625b5691ee3381e107ccbe1ff42398b1Nick KralevichSQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
48978fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich
48988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich/*
4899a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Test For Auto-Commit Mode
4900a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {autocommit mode}
49017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4902a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_get_autocommit() interface returns non-zero or
49037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** zero if the given database connection is or is not in autocommit mode,
4904a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** respectively.  ^Autocommit mode is on by default.
4905a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Autocommit mode is disabled by a [BEGIN] statement.
4906a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
49077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
49087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If certain kinds of errors occur on a statement within a multi-statement
4909a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
49107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
49117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** transaction might be rolled back automatically.  The only way to
4912a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** find out whether SQLite automatically rolled back the transaction after
49137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** an error is to use this function.
49147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4915a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If another thread changes the autocommit status of the database
4916a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection while this routine is running, then the return value
4917a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is undefined.
49187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
49193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_get_autocommit(sqlite3*);
49207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
49217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4922a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Find The Database Handle Of A Prepared Statement
4923a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4924a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_db_handle interface returns the [database connection] handle
4925a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to which a [prepared statement] belongs.  ^The [database connection]
4926a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned by sqlite3_db_handle is the same [database connection]
4927a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that was the first argument
4928a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
4929a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** create the statement in the first place.
4930a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
49313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_db_handle(sqlite3_stmt*);
4932a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
4933a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
493490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Return The Filename For A Database Connection
493590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
493690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
493790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** associated with database N of connection D.  ^The main database file
493890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** has the name "main".  If there is no attached database N on the database
493990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** connection D, or if database N is a temporary or in-memory database, then
494090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a NULL pointer is returned.
494190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
494290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The filename returned by this function is the output of the
494390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** xFullPathname method of the [VFS].  ^In other words, the filename
494490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** will be an absolute pathname, even if the filename used
494590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to open the database originally was a URI or relative pathname.
494690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
49473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API const char *SQLITE_STDCALL sqlite3_db_filename(sqlite3 *db, const char *zDbName);
494890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
494990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
4950c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** CAPI3REF: Determine if a database is read-only
4951c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown**
4952c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
4953c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** of connection D is read-only, 0 if it is read/write, or -1 if N is not
4954c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** the name of a database on connection D.
4955c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown*/
49563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
4957c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown
4958c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown/*
4959a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Find the next prepared statement
49607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4961a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This interface returns a pointer to the next [prepared statement] after
4962a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
4963a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then this interface returns a pointer to the first prepared statement
4964a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** associated with the database connection pDb.  ^If no prepared statement
4965a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** satisfies the conditions of this routine, it returns NULL.
49667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4967a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [database connection] pointer D in a call to
4968a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_next_stmt(D,S)] must refer to an open database
4969a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection and in particular must not be a NULL pointer.
49707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
49713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_stmt *SQLITE_STDCALL sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
49727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
49737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
4974a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Commit And Rollback Notification Callbacks
49757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
4976a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_commit_hook() interface registers a callback
4977a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function to be invoked whenever a transaction is [COMMIT | committed].
4978a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Any callback set by a previous call to sqlite3_commit_hook()
49797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for the same database connection is overridden.
4980a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_rollback_hook() interface registers a callback
4981a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
4982a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Any callback set by a previous call to sqlite3_rollback_hook()
49837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for the same database connection is overridden.
4984a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The pArg argument is passed through to the callback.
4985a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the callback on a commit hook function returns non-zero,
4986a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the commit is converted into a rollback.
4987a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
4988a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
4989a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** return the P argument from the previous call of the same function
4990a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on the same [database connection] D, or NULL for
4991a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the first call for each function on D.
4992a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
499390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The commit and rollback hook callbacks are not reentrant.
4994a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The callback implementation must not do anything that will modify
4995a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the database connection that invoked the callback.  Any actions
4996a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to modify the database connection must be deferred until after the
4997a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** completion of the [sqlite3_step()] call that triggered the commit
4998a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or rollback hook in the first place.
499990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Note that running any other SQL statements, including SELECT statements,
500090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
500190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the database connections for the meaning of "modify" in this paragraph.
5002a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5003a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Registering a NULL function disables the callback.
5004a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5005a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When the commit hook callback routine returns zero, the [COMMIT]
5006a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** operation is allowed to continue normally.  ^If the commit hook
5007a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
5008a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The rollback hook is invoked on a rollback that results from a commit
5009a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** hook returning non-zero, just as it would be with any other rollback.
5010a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5011a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^For the purposes of this API, a transaction is said to have been
50127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** rolled back if an explicit "ROLLBACK" statement is executed, or
50137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** an error or constraint causes an implicit rollback to occur.
5014a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The rollback callback is not invoked if a transaction is
50157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** automatically rolled back because the database connection is closed.
50167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5017a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also the [sqlite3_update_hook()] interface.
50187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
50193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
50203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
50217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
50227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5023a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Data Change Notification Callbacks
50247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5025a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_update_hook() interface registers a callback function
5026a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with the [database connection] identified by the first argument
50278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to be invoked whenever a row is updated, inserted or deleted in
50288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** a rowid table.
5029a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Any callback set by a previous call to this function
5030a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for the same database connection is overridden.
50317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The second argument is a pointer to the function to invoke when a
50338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** row is updated, inserted or deleted in a rowid table.
5034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first argument to the callback is a copy of the third argument
5035a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to sqlite3_update_hook().
5036a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
5037a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [SQLITE_UPDATE], depending on the operation that caused the callback
5038a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to be invoked.
5039a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The third and fourth arguments to the callback contain pointers to the
5040a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database and table name containing the affected row.
5041a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The final callback parameter is the [rowid] of the row.
5042a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^In the case of an update, this is the [rowid] after the update takes place.
5043a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5044a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The update hook is not invoked when internal system tables are
5045a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** modified (i.e. sqlite_master and sqlite_sequence).)^
50468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
5047a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5048a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^In the current implementation, the update hook
5049a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not invoked when duplication rows are deleted because of an
5050a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
5051a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** invoked when rows are deleted using the [truncate optimization].
5052a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The exceptions defined in this paragraph might change in a future
5053a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** release of SQLite.
5054a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5055a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The update hook implementation must not do anything that will modify
5056a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the database connection that invoked the update hook.  Any actions
5057a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to modify the database connection must be deferred until after the
5058a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** completion of the [sqlite3_step()] call that triggered the update hook.
5059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
5060a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database connections for the meaning of "modify" in this paragraph.
5061a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5062a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_update_hook(D,C,P) function
5063a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returns the P argument from the previous call
5064a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on the same [database connection] D, or NULL for
5065a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the first call on D.
5066a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5067a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
5068a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interfaces.
50697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
50703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_update_hook(
50717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
50727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
50737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void*
50747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
50757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
50767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5077a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Enable Or Disable Shared Pager Cache
50787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5079a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This routine enables or disables the sharing of the database cache
5080a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and schema data structures between [database connection | connections]
5081a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the same database. Sharing is enabled if the argument is true
5082a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and disabled if the argument is false.)^
50837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5084a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Cache sharing is enabled and disabled for an entire process.
5085a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
5086a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sharing was enabled or disabled for each thread separately.
50877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5088a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The cache sharing mode set by this interface effects all subsequent
50897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
50907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Existing database connections continue use the sharing mode
5091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that was in effect at the time they were opened.)^
50927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5093a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
5094a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** successfully.  An [error code] is returned otherwise.)^
50957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5096a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Shared cache is disabled by default. But this might change in
50977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** future releases of SQLite.  Applications that care about shared
50987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** cache setting should set it explicitly.
50997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
51003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
51013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and will always return SQLITE_MISUSE. On those systems,
51023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** shared cache mode should be enabled per-database connection via
51033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
51043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
51058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** This interface is threadsafe on processors where writing a
51068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** 32-bit integer is atomic.
51078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
5108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See Also:  [SQLite Shared-Cache Mode]
51097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
51103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_enable_shared_cache(int);
51117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
51127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Attempt To Free Heap Memory
5114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5115a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_release_memory() interface attempts to free N bytes
5116a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of heap memory by deallocating non-essential memory allocations
5117a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** held by the database library.   Memory used to cache database
5118a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pages to improve performance is an example of non-essential memory.
5119a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^sqlite3_release_memory() returns the number of bytes actually freed,
5120a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** which might be more or less than the amount requested.
5121de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_release_memory() routine is a no-op returning zero
5122de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
512390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
512490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** See also: [sqlite3_db_release_memory()]
51257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
51263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_release_memory(int);
51277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
51287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
512990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Free Memory Used By A Database Connection
513090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
513190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
513290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** memory as possible from database connection D. Unlike the
51338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_release_memory()] interface, this interface is in effect even
51348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
513590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** omitted.
513690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
513790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** See also: [sqlite3_release_memory()]
513890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
51393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_db_release_memory(sqlite3*);
514090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
514190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
5142a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Impose A Limit On Heap Size
51437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5144de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
5145de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** soft limit on the amount of heap memory that may be allocated by SQLite.
5146de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite strives to keep heap memory utilization below the soft heap
5147de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** limit by reducing the number of pages held in the page cache
5148de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** as heap memory usages approaches the limit.
5149de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The soft heap limit is "soft" because even though SQLite strives to stay
5150de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** below the limit, it will exceed the limit rather than generate
5151de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
5152de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** is advisory only.
51537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5154de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The return value from sqlite3_soft_heap_limit64() is the size of
515590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the soft heap limit prior to the call, or negative in the case of an
515690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** error.  ^If the argument N is negative
5157de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** then no change is made to the soft heap limit.  Hence, the current
5158de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** size of the soft heap limit can be determined by invoking
5159de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** sqlite3_soft_heap_limit64() with a negative argument.
51607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5161de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the argument N is zero then the soft heap limit is disabled.
51627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5163de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(The soft heap limit is not enforced in the current implementation
5164de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** if one or more of following conditions are true:
51657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5166de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <ul>
5167de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> The soft heap limit is set to zero.
5168de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> Memory accounting is disabled using a combination of the
5169de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
5170de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
517190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <li> An alternative page cache implementation is specified using
517290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
5173de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <li> The page cache allocates from its own memory pool supplied
5174de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
5175de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**      from the heap.
5176de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </ul>)^
5177de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5178de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
5179de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
5180de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
5181de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the soft heap limit is enforced on every memory allocation.  Without
5182de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
5183de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** when memory is allocated by the page cache.  Testing suggests that because
5184de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the page cache is the predominate memory user in SQLite, most
5185de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** applications will achieve adequate soft heap limit enforcement without
5186de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5187de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5188de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The circumstances under which SQLite will enforce the soft heap limit may
5189de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** changes in future releases of SQLite.
51907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
51913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_soft_heap_limit64(sqlite3_int64 N);
5192de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
5193de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori/*
5194de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** CAPI3REF: Deprecated Soft Heap Limit Interface
5195de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** DEPRECATED
5196de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5197de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
5198de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** interface.  This routine is provided for historical compatibility
5199de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** only.  All new applications should use the
5200de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_soft_heap_limit64()] interface rather than this one.
5201de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*/
52023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_soft_heap_limit(int N);
5203de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
52047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
52057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5206a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Extract Metadata About A Column Of A Table
52077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
52083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
52093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** information about column C of table T in database D
52103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
52113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** interface returns SQLITE_OK and fills in the non-NULL pointers in
52123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the final five arguments with appropriate values if the specified
52133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** column exists.  ^The sqlite3_table_column_metadata() interface returns
52143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** SQLITE_ERROR and if the specified column does not exist.
52153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the column-name parameter to sqlite3_table_column_metadata() is a
52163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** NULL pointer, then this routine simply checks for the existance of the
52173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
52183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** does not.
52197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5220a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The column is identified by the second, third and fourth parameters to
52213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** this function. ^(The second parameter is either the name of the database
5222a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (i.e. "main", "temp", or an attached database) containing the specified
52233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** table or NULL.)^ ^If it is NULL, then all attached databases are searched
5224a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for the table using the same algorithm used by the database engine to
52257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** resolve unqualified table references.
52267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5227a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The third and fourth parameters to this function are the table and column
52283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** name of the desired column, respectively.
52297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5230a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Metadata is returned by writing to the memory locations passed as the 5th
5231a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and subsequent parameters to this function. ^Any of these arguments may be
5232a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** NULL, in which case the corresponding element of metadata is omitted.
52337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5234a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<blockquote>
5235a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <table border="1">
5236a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><th> Parameter <th> Output<br>Type <th>  Description
52377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5238a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 5th <td> const char* <td> Data type
5239a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5240a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
5241a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
5242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
5243a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </table>
5244a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </blockquote>)^
52457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5246a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The memory pointed to by the character pointers returned for the
52473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** declaration type and collation sequence is valid until the next
5248a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call to any SQLite API function.
52497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5250a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the specified table is actually a view, an [error code] is returned.
52517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
52523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
52533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is not a [WITHOUT ROWID] table and an
5254a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
5255a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameters are set for the explicitly declared column. ^(If there is no
52563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [INTEGER PRIMARY KEY] column, then the outputs
52573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** for the [rowid] are set as follows:
52587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
52597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <pre>
52607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**     data type: "INTEGER"
52617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**     collation sequence: "BINARY"
52627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**     not null: 0
52637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**     primary key: 1
52647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**     auto increment: 0
5265a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </pre>)^
52667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
52673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^This function causes all database schemas to be read from disk and
52683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** parsed, if that has not already been done, and returns an error if
52693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** any errors are encountered while loading the schema.
52707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
52713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_table_column_metadata(
52727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,                /* Connection handle */
52737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zDbName,        /* Database name or NULL */
52747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zTableName,     /* Table name */
52757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zColumnName,    /* Column name */
52767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char const **pzDataType,    /* OUTPUT: Declared data type */
52777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
52787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
52797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
52807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
52817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
52827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
52837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5284a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Load An Extension
5285a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5286a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This interface loads an SQLite extension library from the named file.
52877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5288a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_load_extension() interface attempts to load an
52898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [SQLite extension] library contained in the file zFile.  If
52908fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the file cannot be loaded directly, attempts are made to load
52918fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** with various operating-system specific extensions added.
52928fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** So for example, if "samplelib" cannot be loaded, then names like
52938fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
52948fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** be tried also.
52957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5296a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The entry point is zProc.
52978fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^(zProc may be 0, in which case SQLite will try to come up with an
52988fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** entry point name on its own.  It first tries "sqlite3_extension_init".
52998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** If that does not work, it constructs a name "sqlite3_X_init" where the
53008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** X is consists of the lower-case equivalent of all ASCII alphabetic
53018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** characters in the filename from the last "/" to the first following
53028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** "." and omitting any initial "lib".)^
5303a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_load_extension() interface returns
5304a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5305a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an error occurs and pzErrMsg is not 0, then the
5306a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_load_extension()] interface shall attempt to
5307a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** fill *pzErrMsg with error message text stored in memory
5308a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** obtained from [sqlite3_malloc()]. The calling function
5309a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** should free this memory by calling [sqlite3_free()].
53107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5311a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Extension loading must be enabled using
5312a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_enable_load_extension()] prior to calling this API,
5313a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** otherwise an error will be returned.
53147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5315a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also the [load_extension() SQL function].
53167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
53173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_load_extension(
53187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,          /* Load the extension into this database connection */
53197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zFile,    /* Name of the shared library containing extension */
53207790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
53217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char **pzErrMsg       /* Put error message here if not 0 */
53227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
53237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
53247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5325a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Enable Or Disable Extension Loading
53267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5327a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^So as not to open security holes in older applications that are
53288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** unprepared to deal with [extension loading], and as a means of disabling
53298fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [extension loading] while evaluating user-entered SQL, the following API
5330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
53317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
53328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^Extension loading is off by default.
5333a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Call the sqlite3_enable_load_extension() routine with onoff==1
5334a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to turn extension loading on and call it with onoff==0 to turn
5335a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it back off again.
53367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
53373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_enable_load_extension(sqlite3 *db, int onoff);
53387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
53397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5340de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** CAPI3REF: Automatically Load Statically Linked Extensions
5341de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5342de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^This interface causes the xEntryPoint() function to be invoked for
5343de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** each new [database connection] that is created.  The idea here is that
53448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** xEntryPoint() is the entry point for a statically linked [SQLite extension]
5345de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** that is to be automatically loaded into all new database connections.
5346de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5347de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(Even though the function prototype shows that xEntryPoint() takes
5348de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** no arguments and returns void, SQLite invokes xEntryPoint() with three
5349de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** arguments and expects and integer result as if the signature of the
5350de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** entry point where as follows:
5351de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5352de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <blockquote><pre>
5353de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** &nbsp;  int xEntryPoint(
5354de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** &nbsp;    sqlite3 *db,
5355de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** &nbsp;    const char **pzErrMsg,
5356de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** &nbsp;    const struct sqlite3_api_routines *pThunk
5357de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** &nbsp;  );
5358de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </pre></blockquote>)^
53597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5360de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
5361de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** point to an appropriate error message (obtained from [sqlite3_mprintf()])
5362de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
5363de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** is NULL before calling the xEntryPoint().  ^SQLite will invoke
5364de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
5365de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
5366de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
5367a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5368de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
5369de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** on the list of automatic extensions is a harmless no-op. ^No entry point
5370de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** will be called more than once for each database connection that is opened.
5371a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
53728fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** See also: [sqlite3_reset_auto_extension()]
53738fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and [sqlite3_cancel_auto_extension()]
53747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
53753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_auto_extension(void (*xEntryPoint)(void));
53767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
53777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
53788fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** CAPI3REF: Cancel Automatic Extension Loading
53798fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
53808fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
53818fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** initialization routine X that was registered using a prior call to
53828fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
53838fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** routine returns 1 if initialization routine X was successfully
53848fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** unregistered and it returns 0 if X was not on the list of initialization
53858fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** routines.
53868fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich*/
53873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
53888fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich
53898fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich/*
5390a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Reset Automatic Extension Loading
53917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5392de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^This interface disables all automatic extensions previously
5393de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** registered using [sqlite3_auto_extension()].
53947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
53953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_reset_auto_extension(void);
53967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
53977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
53987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The interface to the virtual-table mechanism is currently considered
53997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to be experimental.  The interface might change in incompatible ways.
54007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If this is a problem for you, do not use the interface at this time.
54017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5402a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When the virtual-table mechanism stabilizes, we will declare the
54037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface fixed, support it indefinitely, and remove this comment.
54047790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
54057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
54067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
54077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Structures used by the virtual table interface
54087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
54097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_vtab sqlite3_vtab;
54107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_index_info sqlite3_index_info;
54117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
54127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_module sqlite3_module;
54137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
54147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5415a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Virtual Table Object
5416a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: sqlite3_module {virtual table module}
5417a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
541890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** This structure, sometimes called a "virtual table module",
5419a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** defines the implementation of a [virtual tables].
5420a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This structure consists mostly of methods for the module.
5421a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5422a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A virtual table module is created by filling in a persistent
5423a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** instance of this structure and passing a pointer to that instance
5424a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
5425a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The registration remains valid until it is replaced by a different
5426a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** module or until the [database connection] closes.  The content
5427a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of this structure must not change while it is registered with
5428a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** any database connection.
54297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
54307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_module {
54317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int iVersion;
54327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xCreate)(sqlite3*, void *pAux,
54337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project               int argc, const char *const*argv,
54347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project               sqlite3_vtab **ppVTab, char**);
54357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xConnect)(sqlite3*, void *pAux,
54367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project               int argc, const char *const*argv,
54377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project               sqlite3_vtab **ppVTab, char**);
54387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
54397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xDisconnect)(sqlite3_vtab *pVTab);
54407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xDestroy)(sqlite3_vtab *pVTab);
54417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
54427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xClose)(sqlite3_vtab_cursor*);
54437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
54447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project                int argc, sqlite3_value **argv);
54457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xNext)(sqlite3_vtab_cursor*);
54467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xEof)(sqlite3_vtab_cursor*);
54477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
54487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
54497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
54507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xBegin)(sqlite3_vtab *pVTab);
54517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xSync)(sqlite3_vtab *pVTab);
54527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xCommit)(sqlite3_vtab *pVTab);
54537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xRollback)(sqlite3_vtab *pVTab);
54547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
54557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
54567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project                       void **ppArg);
54577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
545890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  /* The methods above are in version 1 of the sqlite_module object. Those
545990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  ** below are for version 2 and greater. */
546090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xSavepoint)(sqlite3_vtab *pVTab, int);
546190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xRelease)(sqlite3_vtab *pVTab, int);
546290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
54637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
54647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
54657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5466a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Virtual Table Indexing Information
54677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: sqlite3_index_info
54687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5469de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The sqlite3_index_info structure and its substructures is used as part
5470de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** of the [virtual table] interface to
5471a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** pass information into and receive the reply from the [xBestIndex]
5472a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** method of a [virtual table module].  The fields under **Inputs** are the
54737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** inputs to xBestIndex and are read-only.  xBestIndex inserts its
54747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** results into the **Outputs** fields.
54757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5476a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The aConstraint[] array records WHERE clause constraints of the form:
54777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5478de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** <blockquote>column OP expr</blockquote>
54797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5480a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
5481de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** stored in aConstraint[].op using one of the
5482de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
5483de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(The index of the column is stored in
5484a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
54857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** expr on the right-hand side can be evaluated (and thus the constraint
5486a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is usable) and false if it cannot.)^
54877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5488a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The optimizer automatically inverts terms of the form "expr OP column"
54897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** and makes other simplifications to the WHERE clause in an attempt to
54907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** get as many WHERE clause terms into the form shown above as possible.
5491a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The aConstraint[] array only reports WHERE clause terms that are
5492a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** relevant to the particular virtual table being queried.
54937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5494a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Information about the ORDER BY clause is stored in aOrderBy[].
5495a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Each term of aOrderBy records a column of the ORDER BY clause.
54967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5497a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [xBestIndex] method must fill aConstraintUsage[] with information
5498a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** about what parameters to pass to xFilter.  ^If argvIndex>0 then
54997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the right-hand side of the corresponding aConstraint[] is evaluated
5500a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
55017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is true, then the constraint is assumed to be fully handled by the
5502a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** virtual table and is not checked again by SQLite.)^
55037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5504a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The idxNum and idxPtr values are recorded and passed into the
5505a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [xFilter] method.
5506a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^[sqlite3_free()] is used to free idxPtr if and only if
5507a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** needToFreeIdxPtr is true.
55087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5509a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
55107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the correct order to satisfy the ORDER BY clause so that no separate
55117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sorting step is required.
55127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
55138fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The estimatedCost value is an estimate of the cost of a particular
55148fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** strategy. A cost of N indicates that the cost of the strategy is similar
55158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to a linear scan of an SQLite table with N rows. A cost of log(N)
55168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** indicates that the expense of the operation is similar to that of a
55178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** binary search on a unique indexed field of an SQLite table with N rows.
55188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
55198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The estimatedRows value is an estimate of the number of rows that
55208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** will be returned by the strategy.
55218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
55228fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
55238fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** structure for SQLite version 3.8.2. If a virtual table extension is
55248fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** used with an SQLite version earlier than 3.8.2, the results of attempting
55258fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to read or write the estimatedRows field are undefined (but are likely
55268fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to included crashing the application). The estimatedRows field should
55278fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** therefore only be used if [sqlite3_libversion_number()] returns a
55288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** value greater than or equal to 3008002.
55297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
55307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_index_info {
55317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  /* Inputs */
55327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nConstraint;           /* Number of entries in aConstraint */
55337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  struct sqlite3_index_constraint {
55347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     int iColumn;              /* Column on left-hand side of constraint */
55357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     unsigned char op;         /* Constraint operator */
55367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     unsigned char usable;     /* True if this constraint is usable */
55377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     int iTermOffset;          /* Used internally - xBestIndex should ignore */
55387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  } *aConstraint;            /* Table of WHERE clause constraints */
55397790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int nOrderBy;              /* Number of terms in the ORDER BY clause */
55407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  struct sqlite3_index_orderby {
55417790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     int iColumn;              /* Column number */
55427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project     unsigned char desc;       /* True for DESC.  False for ASC. */
55437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  } *aOrderBy;               /* The ORDER BY clause */
55447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  /* Outputs */
55457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  struct sqlite3_index_constraint_usage {
55467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
55477790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project    unsigned char omit;      /* Do not code a test for this constraint */
55487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  } *aConstraintUsage;
55497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int idxNum;                /* Number used to identify the index */
55507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
55517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
55527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int orderByConsumed;       /* True if output is already ordered */
55538fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  double estimatedCost;           /* Estimated cost of using this index */
55548fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  /* Fields below are only available in SQLite 3.8.2 and later */
55558fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
55567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
5557de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
5558de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori/*
5559de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** CAPI3REF: Virtual Table Constraint Operator Codes
5560de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
5561de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** These macros defined the allowed values for the
5562de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [sqlite3_index_info].aConstraint[].op field.  Each value represents
5563de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** an operator that is part of a constraint term in the wHERE clause of
5564de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** a query that uses a [virtual table].
5565de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*/
55667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_EQ    2
55677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_GT    4
55687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_LE    8
55697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_LT    16
55707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_GE    32
55717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_INDEX_CONSTRAINT_MATCH 64
55727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
55737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5574a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Register A Virtual Table Implementation
5575a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5576a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^These routines are used to register a new [virtual table module] name.
5577a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Module names must be registered before
5578a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** creating a new [virtual table] using the module and before using a
5579a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** preexisting [virtual table] for the module.
5580a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5581a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The module name is registered on the [database connection] specified
5582a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by the first parameter.  ^The name of the module is given by the
5583a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** second parameter.  ^The third parameter is a pointer to
5584a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the implementation of the [virtual table module].   ^The fourth
5585a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter is an arbitrary client data pointer that is passed through
5586a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** into the [xCreate] and [xConnect] methods of the virtual table module
5587a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when a new virtual table is be being created or reinitialized.
5588a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5589a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_create_module_v2() interface has a fifth parameter which
5590a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is a pointer to a destructor for the pClientData.  ^SQLite will
5591a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** invoke the destructor function (if it is not NULL) when SQLite
559295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** no longer needs the pClientData pointer.  ^The destructor will also
559395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** be invoked if the call to sqlite3_create_module_v2() fails.
559495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The sqlite3_create_module()
5595a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface is equivalent to sqlite3_create_module_v2() with a NULL
5596a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** destructor.
55977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
55983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_module(
55997790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,               /* SQLite connection to register module with */
56007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zName,         /* Name of the module */
5601a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const sqlite3_module *p,   /* Methods for the module */
5602a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *pClientData          /* Client data for xCreate/xConnect */
56037790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
56043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_create_module_v2(
56057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3 *db,               /* SQLite connection to register module with */
56067790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zName,         /* Name of the module */
5607a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const sqlite3_module *p,   /* Methods for the module */
5608a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *pClientData,         /* Client data for xCreate/xConnect */
56097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  void(*xDestroy)(void*)     /* Module destructor function */
56107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
56117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5613a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Virtual Table Instance Object
56147790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** KEYWORDS: sqlite3_vtab
5615a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5616a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Every [virtual table module] implementation uses a subclass
5617a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of this object to describe a particular instance
5618a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the [virtual table].  Each subclass will
5619a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be tailored to the specific needs of the module implementation.
5620a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The purpose of this superclass is to define certain fields that are
5621a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** common to all module implementations.
5622a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5623a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Virtual tables methods can set an error message by assigning a
5624a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
5625a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** take care that any prior string is freed by a call to [sqlite3_free()]
5626a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prior to assigning a new string to zErrMsg.  ^After the error message
56277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is delivered up to the client application, the string will be automatically
5628a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** freed by sqlite3_free() and the zErrMsg field will be zeroed.
56297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
56307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_vtab {
56317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const sqlite3_module *pModule;  /* The module for this virtual table */
56323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  int nRef;                       /* Number of open cursors */
56337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
56347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  /* Virtual table implementations will typically add additional fields */
56357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
56367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5638a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Virtual Table Cursor Object
5639a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
56407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5641a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Every [virtual table module] implementation uses a subclass of the
5642a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** following structure to describe cursors that point into the
5643a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [virtual table] and are used
56447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to loop through the virtual table.  Cursors are created using the
5645a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
5646a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
5647a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
5648a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of the module.  Each module implementation will define
56497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the content of a cursor structure to suit its own needs.
56507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
56517790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This superclass exists in order to define fields of the cursor that
56527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are common to all implementations.
56537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
56547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projectstruct sqlite3_vtab_cursor {
56557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
56567790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  /* Virtual table implementations will typically add additional fields */
56577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project};
56587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5660a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Declare The Schema Of A Virtual Table
56617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5662a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [xCreate] and [xConnect] methods of a
5663a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [virtual table module] call this interface
56647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to declare the format (the names and datatypes of the columns) of
56657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the virtual tables they implement.
56667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
56673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_declare_vtab(sqlite3*, const char *zSQL);
56687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5670a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Overload A Function For A Virtual Table
56717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5672a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Virtual tables can provide alternative implementations of functions
5673a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** using the [xFindFunction] method of the [virtual table module].
5674a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** But global versions of those functions
5675a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** must exist in order to be overloaded.)^
56767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5677a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This API makes sure a global version of a function with a particular
56787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** name and number of parameters exists.  If no such function exists
5679a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** before this API is called, a new function is created.)^  ^The implementation
56807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of the new function always causes an exception to be thrown.  So
56817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the new function is not good for anything by itself.  Its only
5682a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** purpose is to be a placeholder function that can be overloaded
5683a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by a [virtual table].
56847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
56853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
56867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
56887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The interface to the virtual-table mechanism defined above (back up
56897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to a comment remarkably similar to this one) is currently considered
56907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** to be experimental.  The interface might change in incompatible ways.
56917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** If this is a problem for you, do not use the interface at this time.
56927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
56937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** When the virtual-table mechanism stabilizes, we will declare the
56947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface fixed, support it indefinitely, and remove this comment.
56957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
56967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
56977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5698a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: A Handle To An Open BLOB
5699a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {BLOB handle} {BLOB handles}
57007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
57017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** An instance of this object represents an open BLOB on which
5702a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
5703a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Objects of this type are created by [sqlite3_blob_open()]
5704a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and destroyed by [sqlite3_blob_close()].
5705a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
5706a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be used to read or write small subsections of the BLOB.
5707a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
57087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
57097790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Projecttypedef struct sqlite3_blob sqlite3_blob;
57107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
57117790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5712a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Open A BLOB For Incremental I/O
57137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5714a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
57157790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** in row iRow, column zColumn, table zTable in database zDb;
5716a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in other words, the same BLOB that would be selected by:
57177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
57187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <pre>
5719a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
5720a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </pre>)^
57217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
57223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(Parameter zDb is not the filename that contains the database, but
57233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** rather the symbolic name of the database. For attached databases, this is
57243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the name that appears after the AS keyword in the [ATTACH] statement.
57253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** For the main database file, the database name is "main". For TEMP
57263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** tables, the database name is "temp".)^
57273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
5728a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the flags parameter is non-zero, then the BLOB is opened for read
57293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and write access. ^If the flags parameter is zero, the BLOB is opened for
57303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** read-only access.
57313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
57323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
57333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** in *ppBlob. Otherwise an [error code] is returned and, unless the error
57343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
57353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the API is not misused, it is always safe to call [sqlite3_blob_close()]
57363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** on *ppBlob after this function it returns.
57373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
57383fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This function fails with SQLITE_ERROR if any of the following are true:
57393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <ul>
57403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Database zDb does not exist)^,
57413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Table zTable does not exist within database zDb)^,
57423fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Table zTable is a WITHOUT ROWID table)^,
57433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Column zColumn does not exist)^,
57443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Row iRow is not present in the table)^,
57453fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(The specified column of row iRow contains a value that is not
57463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**         a TEXT or BLOB value)^,
57473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
57483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**         constraint and the blob is being opened for read/write access)^,
57493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
57503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**         column zColumn is part of a [child key] definition and the blob is
57513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**         being opened for read/write access)^.
57523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </ul>
57533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
57543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Unless it returns SQLITE_MISUSE, this function sets the
57553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [database connection] error code and message accessible via
57563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
57573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
5758a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5759a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If the row that a BLOB handle points to is modified by an
5760a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
5761a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the BLOB handle is marked as "expired".
5762a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This is true if any column of the row is changed, even a column
5763a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** other than the one the BLOB handle is open on.)^
5764a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
576590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
5766a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Changes written into a BLOB prior to the BLOB expiring are not
5767a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** rolled back by the expiration of the BLOB.  Such changes will eventually
5768a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** commit if the transaction continues to completion.)^
5769a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5770a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
5771a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the opened blob.  ^The size of a blob may not be changed by this
5772a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface.  Use the [UPDATE] SQL command to change the size of a
5773a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** blob.
5774a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5775a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
57763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and the built-in [zeroblob] SQL function may be used to create a
57773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** zero-filled blob to read or write using the incremental-blob interface.
5778a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5779a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** To avoid a resource leak, every open [BLOB handle] should eventually
5780a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be released by a call to [sqlite3_blob_close()].
57817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
57823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_blob_open(
57837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3*,
57847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zDb,
57857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zTable,
57867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  const char *zColumn,
57877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_int64 iRow,
57887790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  int flags,
57897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project  sqlite3_blob **ppBlob
57907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project);
57917790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
57927790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
579395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** CAPI3REF: Move a BLOB Handle to a New Row
579495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
579595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^This function is used to move an existing blob handle so that it points
579695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** to a different row of the same database table. ^The new row is identified
579795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** by the rowid value passed as the second argument. Only the row can be
579895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** changed. ^The database, table and column on which the blob handle is open
579995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** remain the same. Moving an existing blob handle to a new row can be
580095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** faster than closing the existing handle and opening a new one.
580195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
580295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
580395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** it must exist and there must be either a blob or text value stored in
580495c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** the nominated column.)^ ^If the new row is not present in the table, or if
580595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** it does not contain a blob or text value, or if another error occurs, an
580695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** SQLite error code is returned and the blob handle is considered aborted.
580795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
580895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
580995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
581095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** always returns zero.
581195c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
581295c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^This function sets the database handle error code and message.
581395c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori*/
58143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_EXPERIMENTAL int SQLITE_STDCALL sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
581595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori
581695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori/*
5817a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Close A BLOB Handle
58187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
58193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
58203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** unconditionally.  Even if this routine returns an error code, the
58213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** handle is still closed.)^
58227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
58233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If the blob handle being closed was opened for read-write access, and if
58243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the database is in auto-commit mode and there are no other open read-write
58253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** blob handles or active write statements, the current transaction is
58263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** committed. ^If an error occurs while committing the transaction, an error
58273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** code is returned and the transaction rolled back.
58287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
58293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Calling this function with an argument that is not a NULL pointer or an
58303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** open blob handle results in undefined behaviour. ^Calling this routine
58313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** with a null pointer (such as would be returned by a failed call to
58323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
58333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is passed a valid open blob handle, the values returned by the
58343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
58357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
58363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_blob_close(sqlite3_blob *);
58377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
58387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5839a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Return The Size Of An Open BLOB
58407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5841a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Returns the size in bytes of the BLOB accessible via the
5842a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** successfully opened [BLOB handle] in its only argument.  ^The
5843a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** incremental blob I/O routines can only read or overwriting existing
5844a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** blob content; they cannot change the size of a blob.
58457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5846a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This routine only works on a [BLOB handle] which has been created
5847a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by a prior successful call to [sqlite3_blob_open()] and which has not
5848a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** been closed by [sqlite3_blob_close()].  Passing any other pointer in
5849a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to this routine results in undefined and probably undesirable behavior.
58507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
58513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_blob_bytes(sqlite3_blob *);
58527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
58537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5854a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Read Data From A BLOB Incrementally
58557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5856a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This function is used to read data from an open [BLOB handle] into a
5857a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** caller-supplied buffer. N bytes of data are copied into buffer Z
5858a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from the open BLOB, starting at offset iOffset.)^
58597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5860a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If offset iOffset is less than N bytes from the end of the BLOB,
5861a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
5862a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** less than zero, [SQLITE_ERROR] is returned and no data is read.
5863a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The size of the blob (and hence the maximum value of N+iOffset)
5864a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be determined using the [sqlite3_blob_bytes()] interface.
58657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5866a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^An attempt to read from an expired [BLOB handle] fails with an
5867a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** error code of [SQLITE_ABORT].
58687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5869a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
5870a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Otherwise, an [error code] or an [extended error code] is returned.)^
58717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5872a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This routine only works on a [BLOB handle] which has been created
5873a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by a prior successful call to [sqlite3_blob_open()] and which has not
5874a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** been closed by [sqlite3_blob_close()].  Passing any other pointer in
5875a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to this routine results in undefined and probably undesirable behavior.
58767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5877a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_blob_write()].
58787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
58793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
58807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
58817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5882a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Write Data Into A BLOB Incrementally
58837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
58843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(This function is used to write data into an open [BLOB handle] from a
58853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** caller-supplied buffer. N bytes of data are copied from the buffer Z
58863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** into the open BLOB, starting at offset iOffset.)^
58873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
58883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
58893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Otherwise, an  [error code] or an [extended error code] is returned.)^
58903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Unless SQLITE_MISUSE is returned, this function sets the
58913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [database connection] error code and message accessible via
58923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
58937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5894a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the [BLOB handle] passed as the first argument was not opened for
5895a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** writing (the flags parameter to [sqlite3_blob_open()] was zero),
5896a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this function returns [SQLITE_READONLY].
58977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
58983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This function may only modify the contents of the BLOB; it is
5899a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not possible to increase the size of a BLOB using this API.
5900a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If offset iOffset is less than N bytes from the end of the BLOB,
59013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [SQLITE_ERROR] is returned and no data is written. The size of the
59023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** BLOB (and hence the maximum value of N+iOffset) can be determined
59033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
59043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** than zero [SQLITE_ERROR] is returned and no data is written.
59057790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5906a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^An attempt to write to an expired [BLOB handle] fails with an
5907a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
5908a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** before the [BLOB handle] expired are not rolled back by the
5909a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** expiration of the handle, though of course those changes might
5910a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** have been overwritten by the statement that expired the BLOB handle
5911a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or by other independent statements.
59127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5913a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This routine only works on a [BLOB handle] which has been created
5914a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by a prior successful call to [sqlite3_blob_open()] and which has not
5915a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** been closed by [sqlite3_blob_close()].  Passing any other pointer in
5916a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to this routine results in undefined and probably undesirable behavior.
59177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5918a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_blob_read()].
59197790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
59203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
59217790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
59227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5923a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Virtual File System Objects
59247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
59257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** A virtual filesystem (VFS) is an [sqlite3_vfs] object
59267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** that SQLite uses to interact
59277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** with the underlying operating system.  Most SQLite builds come with a
59287790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** single default VFS that is appropriate for the host computer.
59297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** New VFSes can be registered and existing VFSes can be unregistered.
59307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The following interfaces are provided.
59317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5932a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
5933a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Names are case sensitive.
5934a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Names are zero-terminated UTF-8 strings.
5935a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If there is no match, a NULL pointer is returned.
5936a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If zVfsName is NULL then the default VFS is returned.
5937a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5938a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^New VFSes are registered with sqlite3_vfs_register().
5939a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
5940a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The same VFS can be registered multiple times without injury.
5941a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^To make an existing VFS into the default VFS, register it again
59427790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** with the makeDflt flag set.  If two different VFSes with the
59437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** same name are registered, the behavior is undefined.  If a
59447790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** VFS is registered with a name that is NULL or an empty string,
59457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** then the behavior is undefined.
59467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5947a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
5948a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If the default VFS is unregistered, another VFS is chosen as
5949a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the default.  The choice for the new VFS is arbitrary.)^
59507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
59513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_vfs *SQLITE_STDCALL sqlite3_vfs_find(const char *zVfsName);
59523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
59533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_vfs_unregister(sqlite3_vfs*);
59547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
59557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
5956a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Mutexes
59577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
59587790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The SQLite core uses these routines for thread
5959a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** synchronization. Though they are intended for internal
59607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** use by SQLite, code that links against SQLite is
59617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** permitted to use any of these routines.
59627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
5963a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The SQLite source code contains multiple implementations
59647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** of these mutex routines.  An appropriate implementation
59653fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is selected automatically at compile-time.  The following
59667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** implementations are available in the SQLite core:
59677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
59687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
596990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <li>   SQLITE_MUTEX_PTHREADS
59707790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>   SQLITE_MUTEX_W32
59717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>   SQLITE_MUTEX_NOOP
59723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </ul>
59737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
59743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The SQLITE_MUTEX_NOOP implementation is a set of routines
5975a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that does no real locking and is appropriate for use in
59763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
59778fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
59788fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** and Windows.
5979a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
59803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
59817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
5982a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation is included with the library. In this case the
5983a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** application must supply a custom mutex implementation using the
5984a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
5985a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** before calling sqlite3_initialize() or any other public sqlite3_
59863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** function that calls sqlite3_initialize().
5987a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
5988a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_mutex_alloc() routine allocates a new
59893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
59903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** routine returns NULL if it is unable to allocate the requested
59913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** mutex.  The argument to sqlite3_mutex_alloc() must one of these
59923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** integer constants:
59937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
59947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <ul>
59957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_FAST
59967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_RECURSIVE
59977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_STATIC_MASTER
59987790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_STATIC_MEM
59999bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** <li>  SQLITE_MUTEX_STATIC_OPEN
60007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_STATIC_PRNG
60017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** <li>  SQLITE_MUTEX_STATIC_LRU
60029bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** <li>  SQLITE_MUTEX_STATIC_PMEM
60039bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** <li>  SQLITE_MUTEX_STATIC_APP1
60049bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** <li>  SQLITE_MUTEX_STATIC_APP2
60053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <li>  SQLITE_MUTEX_STATIC_APP3
60063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </ul>
60077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6008a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
6009a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** cause sqlite3_mutex_alloc() to create
6010a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
6011a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
60127790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The mutex implementation does not need to make a distinction
60137790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
60143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** not want to.  SQLite will only request a recursive mutex in
60153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** cases where it really needs one.  If a faster non-recursive mutex
60167790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** implementation is available on the host platform, the mutex subsystem
60177790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** might return such a mutex in response to SQLITE_MUTEX_FAST.
60187790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6019a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
6020a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
60213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** a pointer to a static preexisting mutex.  ^Nine static mutexes are
60227790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** used by the current version of SQLite.  Future versions of SQLite
60237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** may add additional static mutexes.  Static mutexes are for internal
60247790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** use by SQLite only.  Applications that use SQLite mutexes should
60257790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
60267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLITE_MUTEX_RECURSIVE.
60277790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6028a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
60297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
60303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** returns a different mutex on every call.  ^For the static
60317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** mutex types, the same mutex is returned on every call that has
6032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the same type number.
60337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_mutex_free() routine deallocates a previously
60353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** allocated dynamic mutex.  Attempting to deallocate a static
60363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** mutex results in undefined behavior.
60377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6038a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
6039a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to enter a mutex.  ^If another thread is already within the mutex,
60407790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
6041a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
6042a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** upon successful entry.  ^(Mutexes created using
60437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
60443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** In such cases, the
60457790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** mutex must be exited an equal number of times before another thread
60463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** can enter.)^  If the same thread tries to enter any mutex other
60473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
60487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6049a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Some systems (for example, Windows 95) do not support the operation
6050a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
60513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** will always return SQLITE_BUSY. The SQLite core only ever uses
60523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_mutex_try() as an optimization so this is acceptable
60533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** behavior.)^
60547790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6055a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_mutex_leave() routine exits a mutex that was
60563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** previously entered by the same thread.   The behavior
60577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** is undefined if the mutex is not currently entered by the
60583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** calling thread or is not currently allocated.
6059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6060a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
6061a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_mutex_leave() is a NULL pointer, then all three routines
6062a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** behave as no-ops.
60637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
60647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
60657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
60663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_mutex *SQLITE_STDCALL sqlite3_mutex_alloc(int);
60673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_mutex_free(sqlite3_mutex*);
60683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_mutex_enter(sqlite3_mutex*);
60693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_mutex_try(sqlite3_mutex*);
60703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_STDCALL sqlite3_mutex_leave(sqlite3_mutex*);
60717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
60727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
6073a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Mutex Methods Object
6074a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6075a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** An instance of this structure defines the low-level routines
6076a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** used to allocate and use mutexes.
6077a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6078a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Usually, the default mutex implementations provided by SQLite are
60793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sufficient, however the application has the option of substituting a custom
6080a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation for specialized deployments or systems for which SQLite
60813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** does not provide a suitable implementation. In this case, the application
6082a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** creates and populates an instance of this structure to pass
6083a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
6084a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Additionally, an instance of this structure can be used as an
6085a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** output variable when querying the system for the current mutex
6086a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
6087a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6088a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The xMutexInit method defined by this structure is invoked as
6089a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** part of system initialization by the sqlite3_initialize() function.
6090de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The xMutexInit routine is called by SQLite exactly once for each
6091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** effective call to [sqlite3_initialize()].
6092a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6093a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The xMutexEnd method defined by this structure is invoked as
6094a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** part of system shutdown by the sqlite3_shutdown() function. The
6095a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation of this method is expected to release all outstanding
6096a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** resources obtained by the mutex methods implementation, especially
6097a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** those obtained by the xMutexInit method.  ^The xMutexEnd()
6098a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface is invoked exactly once for each call to [sqlite3_shutdown()].
6099a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6100a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The remaining seven methods defined by this structure (xMutexAlloc,
6101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
6102a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xMutexNotheld) implement the following interfaces (respectively):
6103a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6104a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <ul>
6105a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_alloc()] </li>
6106a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_free()] </li>
6107a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_enter()] </li>
6108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_try()] </li>
6109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_leave()] </li>
6110a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_held()] </li>
6111a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <li>  [sqlite3_mutex_notheld()] </li>
6112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </ul>)^
6113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The only difference is that the public sqlite3_XXX functions enumerated
6115a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** above silently ignore any invocations that pass a NULL pointer instead
6116a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of a valid mutex handle. The implementations of the methods defined
6117a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by this structure are not required to handle this case, the results
6118a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of passing a NULL pointer instead of a valid mutex handle are undefined
6119a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (i.e. it is acceptable to provide an implementation that segfaults if
6120a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is passed a NULL pointer).
6121a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
61223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The xMutexInit() method must be threadsafe.  It must be harmless to
6123de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** invoke xMutexInit() multiple times within the same process and without
6124a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** intervening calls to xMutexEnd().  Second and subsequent calls to
6125a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xMutexInit() must be no-ops.
6126a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
61273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
61283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
6129a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
6130a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory allocation for a fast or recursive mutex.
6131a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6132a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
6133a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** called, but only if the prior call to xMutexInit returned SQLITE_OK.
6134a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If xMutexInit fails in any way, it is expected to clean up after itself
6135a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prior to returning.
6136a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6137a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noritypedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
6138a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noristruct sqlite3_mutex_methods {
6139a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xMutexInit)(void);
6140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xMutexEnd)(void);
6141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3_mutex *(*xMutexAlloc)(int);
6142a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xMutexFree)(sqlite3_mutex *);
6143a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xMutexEnter)(sqlite3_mutex *);
6144a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xMutexTry)(sqlite3_mutex *);
6145a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xMutexLeave)(sqlite3_mutex *);
6146a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xMutexHeld)(sqlite3_mutex *);
6147a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xMutexNotheld)(sqlite3_mutex *);
6148a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori};
6149a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6150a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6151a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Mutex Verification Routines
61527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
61537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
61543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** are intended for use inside assert() statements.  The SQLite core
61557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** never uses these routines except inside an assert() and applications
61563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** are advised to follow the lead of the core.  The SQLite core only
61577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** provides implementations for these routines when it is compiled
61583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** with the SQLITE_DEBUG flag.  External mutex implementations
61597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are only required to provide these routines if SQLITE_DEBUG is
61607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** defined and if NDEBUG is not defined.
61617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
61623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** These routines should return true if the mutex in their argument
6163a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is held or not held, respectively, by the calling thread.
61647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
61653fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The implementation is not required to provide versions of these
6166a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routines that actually work. If the implementation does not provide working
6167a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** versions of these routines, it should at least provide stubs that always
6168a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** return true so that one does not get spurious assertion failures.
61697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
61703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If the argument to sqlite3_mutex_held() is a NULL pointer then
6171a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the routine should return 1.   This seems counter-intuitive since
617290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** clearly the mutex cannot be held if it does not exist.  But
61737790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the reason the mutex does not exist is because the build is not
61747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** using mutexes.  And we do not want the assert() containing the
61757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** call to sqlite3_mutex_held() to fail, so a non-zero return is
61763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the appropriate thing to do.  The sqlite3_mutex_notheld()
61777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** interface should also return 1 when given a NULL pointer.
61787790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
6179a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#ifndef NDEBUG
61803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_mutex_held(sqlite3_mutex*);
61813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_mutex_notheld(sqlite3_mutex*);
6182a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#endif
61837790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
61847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
6185a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Mutex Types
6186a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6187a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [sqlite3_mutex_alloc()] interface takes a single argument
6188a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** which is one of these integer constants.
61897790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6190a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The set of static mutexes may change from one SQLite release to the
6191a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** next.  Applications that override the built-in mutex logic must be
6192a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** prepared to accommodate additional static mutexes.
61937790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
61947790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_FAST             0
61957790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_RECURSIVE        1
61967790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_STATIC_MASTER    2
61977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
6198a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
6199a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
62007790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
62017790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
620290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
620390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
62049bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
62059bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
62069bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
62077790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
62087790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
6209a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Retrieve the mutex for a database connection
62107790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6211a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This interface returns a pointer the [sqlite3_mutex] object that
6212a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** serializes access to the [database connection] given in the argument
6213a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when the [threading mode] is Serialized.
6214a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the [threading mode] is Single-thread or Multi-thread then this
6215a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** routine returns a NULL pointer.
6216a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
62173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_mutex *SQLITE_STDCALL sqlite3_db_mutex(sqlite3*);
6218a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6219a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6220a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Low-Level Control Of Database Files
6221a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6222a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_file_control()] interface makes a direct call to the
62237790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** xFileControl method for the [sqlite3_io_methods] object associated
6224a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** with a particular database identified by the second argument. ^The
622595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** name of the database is "main" for the main database or "temp" for the
6226a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** TEMP database, or the name that appears after the AS keyword for
6227a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** databases that are added using the [ATTACH] SQL command.
6228a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A NULL pointer can be used in place of "main" to refer to the
6229a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** main database file.
6230a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The third and fourth parameters to this routine
62317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** are passed directly through to the second and third parameters of
6232a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the xFileControl method.  ^The return value of the xFileControl
62337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** method becomes the return value of this routine.
62347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
623595c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
623695c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** a pointer to the underlying [sqlite3_file] object to be written into
623795c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** the space pointed to by the 4th parameter.  ^The SQLITE_FCNTL_FILE_POINTER
623895c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** case is a short-circuit path which does not actually invoke the
623995c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori** underlying sqlite3_io_methods.xFileControl method.
624095c34edce550d0869113085e0cd1b6b09e8fe38bVasu Nori**
6241a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the second parameter (zDbName) does not match the name of any
6242a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** open database file, then SQLITE_ERROR is returned.  ^This error
62437790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** code is not remembered and will not be recalled by [sqlite3_errcode()]
6244a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or [sqlite3_errmsg()].  The underlying xFileControl method might
6245a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** also return SQLITE_ERROR.  There is no way to distinguish between
62467790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** an incorrect zDbName and an SQLITE_ERROR return from the underlying
6247a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xFileControl method.
62487790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
62497790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** See also: [SQLITE_FCNTL_LOCKSTATE]
62507790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
62513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
62527790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
62537790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
6254a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Testing Interface
62557790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6256a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_test_control() interface is used to read out internal
62577790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** state of SQLite and to inject faults into SQLite for testing
6258a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** purposes.  ^The first parameter is an operation code that determines
62597790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** the number, meaning, and operation of all subsequent parameters.
62607790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
62617790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** This interface is not for use by applications.  It exists solely
62627790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** for verifying the correct operation of the SQLite library.  Depending
62637790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** on how the SQLite library is compiled, this interface might not exist.
62647790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
62657790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** The details of the operation codes, their meanings, the parameters
62667790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** they take, and what they do are all subject to change without notice.
62677790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Unlike most of the SQLite API, this function is not guaranteed to
62687790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** operate consistently from one release to the next.
62697790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
62703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_CDECL sqlite3_test_control(int op, ...);
62717790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
62727790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
6273a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Testing Interface Operation Codes
62747790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
62757790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** These constants are the valid operation code parameters used
62767790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** as the first argument to [sqlite3_test_control()].
62777790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
6278a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These parameters and their meanings are subject to change
62797790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** without notice.  These values are for testing purposes only.
62807790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Applications should not use any of these parameters or the
62817790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** [sqlite3_test_control()] interface.
62827790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
6283a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_FIRST                    5
62847790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TESTCTRL_PRNG_SAVE                5
62857790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TESTCTRL_PRNG_RESTORE             6
62867790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TESTCTRL_PRNG_RESET               7
62877790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#define SQLITE_TESTCTRL_BITVEC_TEST              8
6288a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_FAULT_INSTALL            9
6289a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
6290a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_PENDING_BYTE            11
6291a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_ASSERT                  12
6292a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_ALWAYS                  13
6293a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_RESERVE                 14
6294a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
6295a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_TESTCTRL_ISKEYWORD               16
629690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
629790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
62983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
62998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
63008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
63011c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define SQLITE_TESTCTRL_BYTEORDER               22
63029bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown#define SQLITE_TESTCTRL_ISINIT                  23
63033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_TESTCTRL_SORTER_MMAP             24
63043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_TESTCTRL_IMPOSTER                25
63053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_TESTCTRL_LAST                    25
6306a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6307a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6308a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: SQLite Runtime Status
6309a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
63103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^These interfaces are used to retrieve runtime status information
6311de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** about the performance of SQLite, and optionally to reset various
6312a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** highwater marks.  ^The first argument is an integer code for
6313a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the specific parameter to measure.  ^(Recognized integer codes
631490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** are of the form [status parameters | SQLITE_STATUS_...].)^
6315a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The current value of the parameter is returned into *pCurrent.
6316a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The highest recorded value is returned in *pHighwater.  ^If the
6317a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** resetFlag is true, then the highest record value is reset after
6318a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** *pHighwater is written.  ^(Some parameters do not record the highest
6319a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value.  For those parameters
6320a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** nothing is written into *pHighwater and the resetFlag is ignored.)^
6321a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Other parameters record only the highwater mark and not the current
6322a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value.  For these latter parameters nothing is written into *pCurrent.)^
6323a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
63243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_status() and sqlite3_status64() routines return
63253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** SQLITE_OK on success and a non-zero [error code] on failure.
6326a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
63273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** If either the current value or the highwater mark is too large to
63283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** be represented by a 32-bit integer, then the values returned by
63293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_status() are undefined.
6330a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6331a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_db_status()]
6332a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
63333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
63343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_status64(
63353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  int op,
63363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  sqlite3_int64 *pCurrent,
63373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  sqlite3_int64 *pHighwater,
63383fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  int resetFlag
63393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich);
6340a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6341a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6342a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6343a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Status Parameters
634490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** KEYWORDS: {status parameters}
6345a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6346a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These integer constants designate various run-time status parameters
6347a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that can be returned by [sqlite3_status()].
6348a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6349a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
635090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
6351a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter is the current amount of memory checked out
6352a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** using [sqlite3_malloc()], either directly or indirectly.  The
6353a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** figure includes calls made to [sqlite3_malloc()] by the application
6354a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and internal memory usage by the SQLite library.  Scratch memory
6355a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
6356a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
6357a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** this parameter.  The amount returned is the sum of the allocation
6358a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
6359a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
636090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
6361a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter records the largest memory allocation request
6362a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
6363a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** internal equivalents).  Only the value returned in the
6364a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** *pHighwater parameter to [sqlite3_status()] is of interest.
6365a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The value written into the *pCurrent parameter is undefined.</dd>)^
6366a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
636790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
636890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter records the number of separate memory allocations
636990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** currently checked out.</dd>)^
6370de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
637190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
6372a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter returns the number of pages used out of the
6373a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [pagecache memory allocator] that was configured using
6374a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_PAGECACHE].  The
6375a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value returned is in pages, not in bytes.</dd>)^
6376a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
637790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
6378a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
6379a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter returns the number of bytes of page cache
6380de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
6381a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** buffer and where forced to overflow to [sqlite3_malloc()].  The
6382a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned value includes allocations that overflowed because they
6383a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** where too large (they were larger than the "sz" parameter to
6384a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
6385a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** no space was left in the page cache.</dd>)^
6386a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
638790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
6388a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter records the largest memory allocation request
6389a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** handed to [pagecache memory allocator].  Only the value returned in the
6390a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** *pHighwater parameter to [sqlite3_status()] is of interest.
6391a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The value written into the *pCurrent parameter is undefined.</dd>)^
6392a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
639390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
6394a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter returns the number of allocations used out of the
6395a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [scratch memory allocator] configured using
6396a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
6397a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in bytes.  Since a single thread may only have one scratch allocation
6398a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** outstanding at time, this parameter also reports the number of threads
6399a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** using scratch memory at the same time.</dd>)^
6400a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
640190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
6402a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter returns the number of bytes of scratch memory
6403de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
6404a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** buffer and where forced to overflow to [sqlite3_malloc()].  The values
6405a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned include overflows because the requested allocation was too
6406a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** larger (that is, because the requested allocation was larger than the
6407a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
6408a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** slots were available.
6409a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dd>)^
6410a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
641190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
6412a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter records the largest memory allocation request
6413a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** handed to [scratch memory allocator].  Only the value returned in the
6414a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** *pHighwater parameter to [sqlite3_status()] is of interest.
6415a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The value written into the *pCurrent parameter is undefined.</dd>)^
6416a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
641790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
6418a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter records the deepest parser stack.  It is only
6419a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
6420a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
6421a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6422a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New status parameters may be added from time to time.
6423a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6424a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_MEMORY_USED          0
6425a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_PAGECACHE_USED       1
6426a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
6427a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_SCRATCH_USED         3
6428a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
6429a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_MALLOC_SIZE          5
6430a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_PARSER_STACK         6
6431a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_PAGECACHE_SIZE       7
6432a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STATUS_SCRATCH_SIZE         8
6433de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#define SQLITE_STATUS_MALLOC_COUNT         9
6434a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6435a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6436a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Database Connection Status
6437a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6438a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This interface is used to retrieve runtime status information
6439a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** about a single [database connection].  ^The first argument is the
6440a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database connection object to be interrogated.  ^The second argument
644171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** is an integer constant, taken from the set of
644290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_DBSTATUS options], that
6443de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** determines the parameter to interrogate.  The set of
644490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_DBSTATUS options] is likely
644571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** to grow in future releases of SQLite.
6446a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6447a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The current value of the requested parameter is written into *pCur
6448a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the highest instantaneous value is written into *pHiwtr.  ^If
6449a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the resetFlg is true, then the highest instantaneous value is
6450a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** reset back down to the current value.
6451a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6452de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
6453de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** non-zero [error code] on failure.
6454de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
6455a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
6456a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
64573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
6458a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6459a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6460a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Status Parameters for database connections
646190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** KEYWORDS: {SQLITE_DBSTATUS options}
6462a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6463a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These constants are the available integer "verbs" that can be passed as
6464a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the second argument to the [sqlite3_db_status()] interface.
6465a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6466a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** New verbs may be added in future releases of SQLite. Existing verbs
6467a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** might be discontinued. Applications should check the return code from
6468a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_db_status()] to make sure that the call worked.
6469a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [sqlite3_db_status()] interface will return a non-zero error code
6470a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if a discontinued or unsupported verb is invoked.
6471a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6472a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
647390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
6474a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>This parameter returns the number of lookaside memory slots currently
6475a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** checked out.</dd>)^
647671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
647790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
647890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter returns the number malloc attempts that were
647990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** satisfied using lookaside memory. Only the high-water value is meaningful;
648090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the current value is always zero.)^
648190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
648290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
648390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
648490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter returns the number malloc attempts that might have
648590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** been satisfied using lookaside memory but failed due to the amount of
648690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** memory requested being larger than the lookaside slot size.
648790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Only the high-water value is meaningful;
648890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the current value is always zero.)^
648990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
649090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
649190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
649290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter returns the number malloc attempts that might have
649390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** been satisfied using lookaside memory but failed due to all lookaside
649490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** memory already being in use.
649590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Only the high-water value is meaningful;
649690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the current value is always zero.)^
649790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
649890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
64993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>This parameter returns the approximate number of bytes of heap
6500de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** memory used by all pager caches associated with the database connection.)^
650171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
6502de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
650390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
65043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>This parameter returns the approximate number of bytes of heap
6505de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** memory used to store the schema for all databases associated
6506de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** with the connection - main, temp, and any [ATTACH]-ed databases.)^
6507de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The full amount of memory used by the schemas is reported, even if the
6508de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** schema memory is shared with other database connections due to
6509de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** [shared cache mode] being enabled.
6510de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
6511de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
651290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
65133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>This parameter returns the approximate number of bytes of heap
6514de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** and lookaside memory used by all prepared statements associated with
6515de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the database connection.)^
6516de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
6517de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </dd>
651890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
651990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
652090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter returns the number of pager cache hits that have
652190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
652290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is always 0.
652390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </dd>
652490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
652590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
652690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>This parameter returns the number of pager cache misses that have
652790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
652890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is always 0.
652990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </dd>
65308fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
65318fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
65328fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd>This parameter returns the number of dirty cache entries that have
65338fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** been written to disk. Specifically, the number of pages written to the
65348fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** wal file in wal mode databases, or the number of pages written to the
65358fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** database file in rollback mode databases. Any pages written as part of
65368fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** transaction rollback or database recovery operations are not included.
65378fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** If an IO or other error occurs while writing a page to disk, the effect
65388fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
65398fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
65408fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** </dd>
65418fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
65428fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
65438fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd>This parameter returns zero for the current value if and only if
65448fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** all foreign key constraints (deferred or immediate) have been
65458fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** resolved.)^  ^The highwater mark is always 0.
65468fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** </dd>
6547a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
6548a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
654990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
655090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_CACHE_USED           1
655190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_SCHEMA_USED          2
655290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_STMT_USED            3
655390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
655490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
655590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
655690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_CACHE_HIT            7
655790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_DBSTATUS_CACHE_MISS           8
65588fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_DBSTATUS_CACHE_WRITE          9
65598fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_DBSTATUS_DEFERRED_FKS        10
65608fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_DBSTATUS_MAX                 10   /* Largest defined DBSTATUS */
6561a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6562a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6563a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6564a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Prepared Statement Status
6565a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6566a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(Each prepared statement maintains various
656790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_STMTSTATUS counters] that measure the number
6568a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of times it has performed specific operations.)^  These counters can
6569a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** be used to monitor the performance characteristics of the prepared
6570a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** statements.  For example, if the number of table steps greatly exceeds
6571a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the number of table searches or result rows, that would tend to indicate
6572a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that the prepared statement is using a full table scan rather than
6573a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an index.
6574a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6575a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(This interface is used to retrieve and reset counter values from
6576a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a [prepared statement].  The first argument is the prepared statement
6577a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** object to be interrogated.  The second argument
657890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is an integer code for a specific [SQLITE_STMTSTATUS counter]
6579a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to be interrogated.)^
6580a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The current value of the requested counter is returned.
6581a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the resetFlg is true, then the counter is reset to zero after this
6582a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** interface call returns.
6583a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6584a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See also: [sqlite3_status()] and [sqlite3_db_status()].
6585a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
65863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
6587a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6588a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6589a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Status Parameters for prepared statements
659090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
6591a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6592a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** These preprocessor macros define integer codes that name counter
6593a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** values associated with the [sqlite3_stmt_status()] interface.
6594a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The meanings of the various counters are as follows:
6595a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6596a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dl>
659790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
6598a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>^This is the number of times that SQLite has stepped forward in
6599a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a table as part of a full table scan.  Large numbers for this counter
6600a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** may indicate opportunities for performance improvement through
6601a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** careful use of indices.</dd>
6602a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
660390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
6604a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <dd>^This is the number of sort operations that have occurred.
6605a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A non-zero value in this counter may indicate an opportunity to
6606a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** improvement performance through careful use of indices.</dd>
6607a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
660890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
660971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <dd>^This is the number of rows inserted into transient indices that
661071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** were created automatically in order to help joins run faster.
661171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** A non-zero value in this counter may indicate an opportunity to
661271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** improvement performance by adding permanent indices that do not
661371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** need to be reinitialized each time the statement is run.</dd>
66148fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
66158fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
66168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <dd>^This is the number of virtual machine operations executed
66178fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** by the prepared statement if that number is less than or equal
66188fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** to 2147483647.  The number of virtual machine operations can be
66198fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** used as a proxy for the total work done by the prepared statement.
66208fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** If the number of virtual machine operations exceeds 2147483647
66218fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** then the value returned by this statement status code is undefined.
66228fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** </dd>
6623a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** </dl>
6624a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6625a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
6626a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori#define SQLITE_STMTSTATUS_SORT              2
662771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori#define SQLITE_STMTSTATUS_AUTOINDEX         3
66288fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#define SQLITE_STMTSTATUS_VM_STEP           4
6629a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6630a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6631a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Custom Page Cache Object
6632a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6633a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_pcache type is opaque.  It is implemented by
6634a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the pluggable module.  The SQLite core has no knowledge of
6635a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** its size or internal structure and never deals with the
6636a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_pcache object except by holding and passing pointers
6637a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the object.
6638a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
663990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** See [sqlite3_pcache_methods2] for additional information.
6640a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6641a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noritypedef struct sqlite3_pcache sqlite3_pcache;
6642a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6643a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
664490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Custom Page Cache Object
664590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
664690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The sqlite3_pcache_page object represents a single page in the
664790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** page cache.  The page cache will allocate instances of this
664890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** object.  Various methods of the page cache use pointers to instances
664990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of this object as parameters or as their return value.
665090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
665190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** See [sqlite3_pcache_methods2] for additional information.
665290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
665390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Browntypedef struct sqlite3_pcache_page sqlite3_pcache_page;
665490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brownstruct sqlite3_pcache_page {
665590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void *pBuf;        /* The content of the page */
665690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void *pExtra;      /* Extra information associated with the page */
665790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown};
665890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
665990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
6660a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Application Defined Page Cache.
6661a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** KEYWORDS: {page cache}
6662a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
666390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
6664a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** register an alternative page cache implementation by passing in an
666590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** instance of the sqlite3_pcache_methods2 structure.)^
6666de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** In many applications, most of the heap memory allocated by
6667de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** SQLite is used for the page cache.
6668de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** By implementing a
6669de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** custom page cache using this API, an application can better control
6670de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the amount of memory consumed by SQLite, the way in which
6671a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that memory is allocated and released, and the policies used to
6672a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** determine exactly which parts of a database file are cached and for
6673a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** how long.
6674a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6675de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The alternative page cache mechanism is an
6676de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** extreme measure that is only needed by the most demanding applications.
6677de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The built-in page cache is recommended for most uses.
6678de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
667990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
6680a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** internal buffer by SQLite within the call to [sqlite3_config].  Hence
6681a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the application may discard the parameter after the call to
6682a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_config()] returns.)^
6683a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
668490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xInit() page cache method]]
6685de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(The xInit() method is called once for each effective
6686de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** call to [sqlite3_initialize()])^
6687a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** (usually only once during the lifetime of the process). ^(The xInit()
668890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
6689de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The intent of the xInit() method is to set up global data structures
6690a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** required by the custom page cache implementation.
6691de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(If the xInit() method is NULL, then the
6692de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** built-in default page cache is used instead of the application defined
6693de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** page cache.)^
6694a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
669590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xShutdown() page cache method]]
6696de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The xShutdown() method is called by [sqlite3_shutdown()].
6697de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** It can be used to clean up
6698a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** any outstanding resources before process shutdown, if required.
6699de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^The xShutdown() method may be NULL.
6700a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6701de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite automatically serializes calls to the xInit method,
6702de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** so the xInit method need not be threadsafe.  ^The
6703a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** xShutdown method is only called from [sqlite3_shutdown()] so it does
6704a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not need to be threadsafe either.  All other methods must be threadsafe
6705a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** in multithreaded applications.
6706a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6707a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^SQLite will never invoke xInit() more than once without an intervening
6708a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call to xShutdown().
6709a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
671090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xCreate() page cache methods]]
6711de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^SQLite invokes the xCreate() method to construct a new cache instance.
6712de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** SQLite will typically create one cache instance for each open database file,
6713a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** though this is not guaranteed. ^The
6714a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** first parameter, szPage, is the size in bytes of the pages that must
671590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** be allocated by the cache.  ^szPage will always a power of two.  ^The
671690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** second parameter szExtra is a number of bytes of extra storage
671790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** associated with each page cache entry.  ^The szExtra parameter will
671890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a number less than 250.  SQLite will use the
671990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** extra szExtra bytes on each page to store metadata about the underlying
672090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** database page on disk.  The value passed into szExtra depends
6721a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on the SQLite version, the target platform, and how SQLite was compiled.
672290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The third argument to xCreate(), bPurgeable, is true if the cache being
672390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** created will be used to cache database pages of a file stored on disk, or
6724de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** false if it is used for an in-memory database. The cache implementation
6725a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** does not have to do anything special based with the value of bPurgeable;
6726a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
6727a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** never invoke xUnpin() except to deliberately delete a page.
6728de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
6729de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** false will always have the "discard" flag set to true.
6730de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^Hence, a cache created with bPurgeable false will
6731a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** never contain any unpinned pages.
6732a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
673390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xCachesize() page cache method]]
6734a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(The xCachesize() method may be called at any time by SQLite to set the
6735a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** suggested maximum cache-size (number of pages stored by) the cache
6736a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** instance passed as the first argument. This is the value configured using
6737de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
6738a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** parameter, the implementation is not required to do anything with this
6739a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** value; it is advisory only.
6740a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
674190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xPagecount() page cache methods]]
6742de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The xPagecount() method must return the number of pages currently
6743de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** stored in the cache, both pinned and unpinned.
6744a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
674590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xFetch() page cache methods]]
6746de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The xFetch() method locates a page in the cache and returns a pointer to
674790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
674890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The pBuf element of the returned sqlite3_pcache_page object will be a
674990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** pointer to a buffer of szPage bytes used to store the content of a
675090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** single database page.  The pExtra element of sqlite3_pcache_page will be
675190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a pointer to the szExtra bytes of extra storage that SQLite has requested
675290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** for each entry in the page cache.
675390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
675490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** The page to be fetched is determined by the key. ^The minimum key value
675590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is 1.  After it has been retrieved using xFetch, the page is considered
675690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** to be "pinned".
6757a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6758de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** If the requested page is already in the page cache, then the page cache
6759a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** implementation must return a pointer to the page buffer with its content
6760de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** intact.  If the requested page is not already in the cache, then the
676190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** cache implementation should use the value of the createFlag
6762de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** parameter to help it determined what action to take:
6763a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6764a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <table border=1 width=85% align=center>
67658fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** <tr><th> createFlag <th> Behavior when page is not already in cache
6766a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
6767a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
6768a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**                 Otherwise return NULL.
6769a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
6770a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**                 NULL if allocating a new page is effectively impossible.
6771de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** </table>
6772a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6773de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
6774de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** will only use a createFlag of 2 after a prior call with a createFlag of 1
6775de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** failed.)^  In between the to xFetch() calls, SQLite may
6776a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** attempt to unpin one or more cache pages by spilling the content of
6777de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** pinned pages to disk and synching the operating system disk cache.
6778a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
677990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xUnpin() page cache method]]
6780a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
6781de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** as its second argument.  If the third parameter, discard, is non-zero,
6782de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** then the page must be evicted from the cache.
6783de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** ^If the discard parameter is
6784de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** zero, then the page may be discarded or retained at the discretion of
6785de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** page cache implementation. ^The page cache implementation
6786a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** may choose to evict unpinned pages at any time.
6787a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6788de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The cache must not perform any reference counting. A single
6789a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call to xUnpin() unpins the page regardless of the number of prior calls
6790de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** to xFetch().
6791a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
679290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xRekey() page cache methods]]
6793de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The xRekey() method is used to change the key value associated with the
6794de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** page passed as the second argument. If the cache
6795de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** previously contains an entry associated with newKey, it must be
6796a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** discarded. ^Any prior cache entry associated with newKey is guaranteed not
6797a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to be pinned.
6798a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6799de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** When SQLite calls the xTruncate() method, the cache must discard all
6800a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** existing cache entries with page numbers (keys) greater than or equal
6801de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** to the value of the iLimit parameter passed to xTruncate(). If any
6802a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** of these pages are pinned, they are implicitly unpinned, meaning that
6803a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** they can be safely discarded.
6804a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
680590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xDestroy() page cache method]]
6806a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The xDestroy() method is used to delete a cache allocated by xCreate().
6807a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** All resources associated with the specified cache should be freed. ^After
6808a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
680990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** handle invalid, and will not use it with any other sqlite3_pcache_methods2
6810a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** functions.
681190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
681290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[the xShrink() page cache method]]
681390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^SQLite invokes the xShrink() method when it wants the page cache to
681490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** free up as much of heap memory as possible.  The page cache implementation
681590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is not obligated to free any memory, but well-behaved implementations should
681690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** do their best.
681790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
681890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Browntypedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
681990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brownstruct sqlite3_pcache_methods2 {
682090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int iVersion;
682190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void *pArg;
682290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xInit)(void*);
682390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xShutdown)(void*);
682490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
682590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
682690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int (*xPagecount)(sqlite3_pcache*);
682790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
682890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
682990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
683090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown      unsigned oldKey, unsigned newKey);
683190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
683290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xDestroy)(sqlite3_pcache*);
683390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  void (*xShrink)(sqlite3_pcache*);
683490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown};
683590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
683690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
683790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** This is the obsolete pcache_methods object that has now been replaced
683890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
683990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** retained in the header file for backwards compatibility only.
6840a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6841a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noritypedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
6842a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noristruct sqlite3_pcache_methods {
6843a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *pArg;
6844a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xInit)(void*);
6845a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xShutdown)(void*);
6846a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
6847a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
6848a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  int (*xPagecount)(sqlite3_pcache*);
6849a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
6850a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
6851a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
6852a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
6853a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xDestroy)(sqlite3_pcache*);
6854a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori};
6855a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
685690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
6857a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6858a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Online Backup Object
6859a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6860a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The sqlite3_backup object records state information about an ongoing
6861a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** online backup operation.  ^The sqlite3_backup object is created by
6862a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a call to [sqlite3_backup_init()] and is destroyed by a call to
6863a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_backup_finish()].
6864a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6865a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See Also: [Using the SQLite Online Backup API]
6866a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
6867a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Noritypedef struct sqlite3_backup sqlite3_backup;
6868a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
6869a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
6870a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Online Backup API.
6871a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6872a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The backup API copies the content of one database into another.
6873a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** It is useful either for creating backups of databases or
6874a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** for copying in-memory databases to or from persistent files.
6875a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6876a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See Also: [Using the SQLite Online Backup API]
6877a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
687890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^SQLite holds a write transaction open on the destination database file
687990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** for the duration of the backup operation.
688090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^The source database is read-locked only while it is being read;
688190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** it is not locked continuously for the entire backup operation.
688290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ^Thus, the backup may be performed on a live source database without
688390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** preventing other database connections from
6884a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** reading or writing to the source database while the backup is underway.
6885a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6886a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(To perform a backup operation:
6887a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   <ol>
6888a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
6889a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**         backup,
6890a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
6891a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**         the data between the two databases, and finally
6892a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**     <li><b>sqlite3_backup_finish()</b> is called to release all resources
6893a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**         associated with the backup operation.
6894a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**   </ol>)^
6895a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** There should be exactly one call to sqlite3_backup_finish() for each
6896a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** successful call to sqlite3_backup_init().
6897a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
689890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
6899a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6900a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
6901a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection] associated with the destination database
6902a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the database name, respectively.
6903a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The database name is "main" for the main database, "temp" for the
6904a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** temporary database, or the name specified after the AS keyword in
6905a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an [ATTACH] statement for an attached database.
6906a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The S and M arguments passed to
6907a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_init(D,N,S,M) identify the [database connection]
6908a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and database name of the source database, respectively.
6909a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The source and destination [database connections] (parameters S and D)
691090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
6911a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an error.
6912a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
69133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^A call to sqlite3_backup_init() will fail, returning SQLITE_ERROR, if
69143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** there is already a read or read-write transaction open on the
69153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** destination database.
69163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
6917a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
691890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** returned and an error code and error message are stored in the
6919a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** destination [database connection] D.
6920a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The error code and message for the failed call to sqlite3_backup_init()
6921a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
6922a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_errmsg16()] functions.
6923a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A successful call to sqlite3_backup_init() returns a pointer to an
6924a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [sqlite3_backup] object.
6925a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
6926a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_finish() functions to perform the specified backup
6927a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** operation.
6928a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
692990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
6930a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6931a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
6932a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the source and destination databases specified by [sqlite3_backup] object B.
6933a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If N is negative, all remaining source pages are copied.
6934a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
693590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** are still more pages to be copied, then the function returns [SQLITE_OK].
6936a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
6937a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from source to destination, then it returns [SQLITE_DONE].
6938a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an error occurs while running sqlite3_backup_step(B,N),
6939a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then an [error code] is returned. ^As well as [SQLITE_OK] and
6940a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
6941a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
6942a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
6943a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
694471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
694571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <ol>
694671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li> the destination database was opened read-only, or
694771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** <li> the destination database is using write-ahead-log journaling
694871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** and the destination and source page sizes differ, or
694990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <li> the destination database is an in-memory database and the
695071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** destination and source page sizes differ.
695171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** </ol>)^
6952a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6953a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
6954a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the [sqlite3_busy_handler | busy-handler function]
6955a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is invoked (if one is specified). ^If the
6956a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** busy-handler returns non-zero before the lock is available, then
6957a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
6958a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step() can be retried later. ^If the source
6959a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection]
6960a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is being used to write to the source database when sqlite3_backup_step()
6961a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
6962a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** case the call to sqlite3_backup_step() can be retried later on. ^(If
6963a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
6964a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_READONLY] is returned, then
6965a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** there is no point in retrying the call to sqlite3_backup_step(). These
6966a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** errors are considered fatal.)^  The application must accept
6967a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that the backup operation has failed and pass the backup operation handle
6968a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** to the sqlite3_backup_finish() to release associated resources.
6969a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6970a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The first call to sqlite3_backup_step() obtains an exclusive lock
6971a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** on the destination file. ^The exclusive lock is not released until either
6972a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_finish() is called or the backup operation is complete
6973a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
6974a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step() obtains a [shared lock] on the source database that
6975a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** lasts for the duration of the sqlite3_backup_step() call.
6976a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Because the source database is not locked between calls to
6977a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step(), the source database may be modified mid-way
6978a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** through the backup process.  ^If the source database is modified by an
6979a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** external process or via a database connection other than the one being
6980a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** used by the backup operation, then the backup will be automatically
6981a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** restarted by the next call to sqlite3_backup_step(). ^If the source
6982a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database is modified by the using the same database connection as is used
6983a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by the backup operation, then the backup database is automatically
6984a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** updated at the same time.
6985a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
698690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
6987a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6988a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
6989a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** application wishes to abandon the backup operation, the application
6990a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
6991a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The sqlite3_backup_finish() interfaces releases all
6992a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** resources associated with the [sqlite3_backup] object.
6993a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
6994a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** active write-transaction on the destination database is rolled back.
6995a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [sqlite3_backup] object is invalid
6996a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and may not be used following a call to sqlite3_backup_finish().
6997a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
6998a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
6999a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step() errors occurred, regardless or whether or not
7000a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step() completed.
7001a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If an out-of-memory condition or IO error occurred during any prior
7002a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
7003a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_finish() returns the corresponding [error code].
7004a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7005a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
7006a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not a permanent error and does not affect the return value of
7007a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_finish().
7008a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
70093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
701090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
7011a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
70123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_backup_remaining() routine returns the number of pages still
70133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to be backed up at the conclusion of the most recent sqlite3_backup_step().
70143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The sqlite3_backup_pagecount() routine returns the total number of pages
70153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** in the source database at the conclusion of the most recent
70163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_backup_step().
70173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The values returned by these functions are only updated by
70183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_backup_step(). If the source database is modified in a way that
70193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** changes the size of the source database or the number of pages remaining,
70203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** those changes are not reflected in the output of sqlite3_backup_pagecount()
70213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and sqlite3_backup_remaining() until after the next
70223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sqlite3_backup_step().)^
7023a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7024a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>Concurrent Usage of Database Handles</b>
7025a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7026a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^The source [database connection] may be used by the application for other
7027a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** purposes while a backup operation is underway or being initialized.
7028a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If SQLite is compiled and configured to support threadsafe database
7029a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connections, then the source database connection may be used concurrently
7030a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from within other threads.
7031a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7032a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** However, the application must guarantee that the destination
7033a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [database connection] is not passed to any other API (by any thread) after
7034a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_init() is called and before the corresponding call to
7035a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_backup_finish().  SQLite does not currently check to see
7036a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** if the application incorrectly accesses the destination [database connection]
7037a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and so no error code is reported, but the operations may malfunction
7038a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** nevertheless.  Use of the destination database connection while a
7039a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** backup is in progress might also also cause a mutex deadlock.
7040a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7041a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If running in [shared cache mode], the application must
7042a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** guarantee that the shared cache used by the destination database
7043a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** is not accessed while the backup is running. In practice this means
7044a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that the application must guarantee that the disk file being
7045a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** backed up to is not accessed by any connection within the process,
7046a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** not just the specific connection that was passed to sqlite3_backup_init().
7047a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7048a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The [sqlite3_backup] object itself is partially threadsafe. Multiple
7049a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** threads may safely make multiple concurrent calls to sqlite3_backup_step().
7050a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
7051a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** APIs are not strictly speaking threadsafe. If they are invoked at the
7052a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** same time as another thread is invoking sqlite3_backup_step() it is
7053a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** possible that they return invalid values.
7054a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
70553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API sqlite3_backup *SQLITE_STDCALL sqlite3_backup_init(
7056a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3 *pDest,                        /* Destination database handle */
7057a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const char *zDestName,                 /* Destination database name */
7058a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3 *pSource,                      /* Source database handle */
7059a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  const char *zSourceName                /* Source database name */
7060a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori);
70613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_backup_step(sqlite3_backup *p, int nPage);
70623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_backup_finish(sqlite3_backup *p);
70633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_backup_remaining(sqlite3_backup *p);
70643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_backup_pagecount(sqlite3_backup *p);
7065a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
7066a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
7067a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: Unlock Notification
7068a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7069a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When running in shared-cache mode, a database operation may fail with
7070a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
7071a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** individual tables within the shared-cache cannot be obtained. See
7072a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
7073a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This API may be used to register a callback that SQLite will invoke
7074a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when the connection currently holding the required lock relinquishes it.
7075a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^This API is only available if the library was compiled with the
7076a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
7077a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7078a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** See Also: [Using the SQLite Unlock Notification Feature].
7079a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7080a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Shared-cache locks are released when a database connection concludes
7081a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** its current transaction, either by committing it or rolling it back.
7082a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7083a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^When a connection (known as the blocked connection) fails to obtain a
7084a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
7085a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** identity of the database connection (the blocking connection) that
7086a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** has locked the required resource is stored internally. ^After an
7087a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** application receives an SQLITE_LOCKED error, it may call the
7088a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_unlock_notify() method with the blocked connection handle as
7089a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the first argument to register for a callback that will be invoked
7090a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** when the blocking connections current transaction is concluded. ^The
7091a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
7092a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** call that concludes the blocking connections transaction.
7093a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7094a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
7095a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** there is a chance that the blocking connection will have already
7096a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
7097a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** If this happens, then the specified callback is invoked immediately,
7098a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** from within the call to sqlite3_unlock_notify().)^
7099a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7100a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^If the blocked connection is attempting to obtain a write-lock on a
7101a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** shared-cache table, and more than one other connection currently holds
7102a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a read-lock on the same table, then SQLite arbitrarily selects one of
7103a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the other connections to use as the blocking connection.
7104a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7105a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^(There may be at most one unlock-notify callback registered by a
7106a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** blocked connection. If sqlite3_unlock_notify() is called when the
7107a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** blocked connection already has a registered unlock-notify callback,
7108a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
7109a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** called with a NULL pointer as its second argument, then any existing
7110de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** unlock-notify callback is canceled. ^The blocked connections
7111a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** unlock-notify callback may also be canceled by closing the blocked
7112a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection using [sqlite3_close()].
7113a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7114a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** The unlock-notify callback is not reentrant. If an application invokes
7115a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** any sqlite3_xxx API functions from within an unlock-notify callback, a
7116a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** crash or deadlock may be the result.
7117a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7118a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
7119a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returns SQLITE_OK.
7120a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7121a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>Callback Invocation Details</b>
7122a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7123a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When an unlock-notify callback is registered, the application provides a
7124a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** single void* pointer that is passed to the callback when it is invoked.
7125a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** However, the signature of the callback function allows SQLite to pass
7126a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** it an array of void* context pointers. The first argument passed to
7127a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** an unlock-notify callback is a pointer to an array of void* pointers,
7128a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** and the second is the number of entries in the array.
7129a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7130a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When a blocking connections transaction is concluded, there may be
7131a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** more than one blocked connection that has registered for an unlock-notify
7132a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** callback. ^If two or more such blocked connections have specified the
7133a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** same callback function, then instead of invoking the callback function
7134a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** multiple times, it is invoked once with the set of void* context pointers
7135a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** specified by the blocked connections bundled together into an array.
7136a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** This gives the application an opportunity to prioritize any actions
7137a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** related to the set of unblocked database connections.
7138a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7139a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>Deadlock Detection</b>
7140a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7141a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Assuming that after registering for an unlock-notify callback a
7142a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** database waits for the callback to be issued before taking any further
7143a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** action (a reasonable assumption), then using this API may cause the
7144a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** application to deadlock. For example, if connection X is waiting for
7145a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** connection Y's transaction to be concluded, and similarly connection
7146a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** Y is waiting on connection X's transaction, then neither connection
7147a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** will proceed and the system may remain deadlocked indefinitely.
7148a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7149a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
7150a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** detection. ^If a given call to sqlite3_unlock_notify() would put the
7151a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** system in a deadlocked state, then SQLITE_LOCKED is returned and no
7152a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** unlock-notify callback is registered. The system is said to be in
7153a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** a deadlocked state if connection A has registered for an unlock-notify
7154a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** callback on the conclusion of connection B's transaction, and connection
7155a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** B has itself registered for an unlock-notify callback when connection
7156a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** A's transaction is concluded. ^Indirect deadlock is also detected, so
7157a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the system is also considered to be deadlocked if connection B has
7158a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** registered for an unlock-notify callback on the conclusion of connection
7159a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** C's transaction, where connection C is waiting on connection A. ^Any
7160a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** number of levels of indirection are allowed.
7161a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7162a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** <b>The "DROP TABLE" Exception</b>
7163a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7164a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
7165a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** always appropriate to call sqlite3_unlock_notify(). There is however,
7166a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
7167a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLite checks if there are any currently executing SELECT statements
7168a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** that belong to the same connection. If there are, SQLITE_LOCKED is
7169a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** returned. In this case there is no "blocking connection", so invoking
7170a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** sqlite3_unlock_notify() results in the unlock-notify callback being
7171a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** invoked immediately. If the application then re-attempts the "DROP TABLE"
7172a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** or "DROP INDEX" query, an infinite loop might be the result.
7173a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7174a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** One way around this problem is to check the extended error code returned
7175a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** by an sqlite3_step() call. ^(If there is a blocking connection, then the
7176a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
7177a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** the special "DROP TABLE/INDEX" case, the extended error code is just
7178a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** SQLITE_LOCKED.)^
7179a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
71803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_unlock_notify(
7181a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  sqlite3 *pBlocked,                          /* Waiting connection */
7182a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
7183a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori  void *pNotifyArg                            /* Argument to pass to xNotify */
7184a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori);
7185a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
7186a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
7187a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori/*
7188a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori** CAPI3REF: String Comparison
7189a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori**
7190c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
7191c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** and extensions to compare the contents of two buffers containing UTF-8
7192c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** strings in a case-independent fashion, using the same definition of "case
7193c82acac4e67711e8d9289b572d334298aeb5d806Jeff Brown** independence" that SQLite uses internally when comparing identifiers.
7194a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori*/
71953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_stricmp(const char *, const char *);
71963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_strnicmp(const char *, const char *, int);
71977790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
7198aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori/*
71998fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** CAPI3REF: String Globbing
72008fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich*
72018fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches
72028fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the glob pattern P, and it returns non-zero if string X does not match
72038fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** the glob pattern P.  ^The definition of glob pattern matching used in
72048fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
72058fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** SQL dialect used by SQLite.  ^The sqlite3_strglob(P,X) function is case
72068fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** sensitive.
72078fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich**
72088fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** Note that this routine returns zero on a match and non-zero if the strings
72098fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
72108fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich*/
72113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_strglob(const char *zGlob, const char *zStr);
72128fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich
72138fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich/*
7214aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori** CAPI3REF: Error Logging Interface
7215aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori**
72168fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich** ^The [sqlite3_log()] interface writes a message into the [error log]
721771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
721871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^If logging is enabled, the zFormat string and subsequent arguments are
721971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** used with [sqlite3_snprintf()] to generate the final output string.
7220aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori**
7221aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori** The sqlite3_log() interface is intended for use by extensions such as
7222aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori** virtual tables, collating functions, and SQL functions.  While there is
7223aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori** nothing to prevent an application from calling sqlite3_log(), doing so
7224aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori** is considered bad form.
7225ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori**
722671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The zFormat string must not be NULL.
722771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
7228ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori** To avoid deadlocks and other threading problems, the sqlite3_log() routine
7229ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori** will not use dynamically allocated memory.  The log message is stored in
7230ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori** a fixed-length buffer on the stack.  If the log message is longer than
7231ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori** a few hundred characters, it will be truncated to the length of the
7232ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori** buffer.
7233aae12b8a5af3a1ac77382b067d9ebb350fbd0644Vasu Nori*/
72343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void SQLITE_CDECL sqlite3_log(int iErrCode, const char *zFormat, ...);
7235ebcc71fd53ce7cf46aff607df2d4bff793837176Vasu Nori
72367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
723771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Write-Ahead Log Commit Hook
723871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
723971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The [sqlite3_wal_hook()] function is used to register a callback that
72403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is invoked each time data is committed to a database in wal mode.
724171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
72423fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The callback is invoked by SQLite after the commit has taken place and
72433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the associated write-lock on the database released)^, so the implementation
724471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** may read, write or [checkpoint] the database as required.
724571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
724671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The first parameter passed to the callback function when it is invoked
724771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** is a copy of the third parameter passed to sqlite3_wal_hook() when
724871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** registering the callback. ^The second is a copy of the database handle.
724971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The third parameter is the name of the database that was written to -
725071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
725171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** is the number of pages currently in the write-ahead log file,
725271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** including those that were just committed.
725371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
725471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** The callback function should normally return [SQLITE_OK].  ^If an error
725571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** code is returned, that error will propagate back up through the
725671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** SQLite code base to cause the statement that provoked the callback
725771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** to report an error, though the commit will have still occurred. If the
725871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
725971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** that does not correspond to any valid SQLite error code, the results
726071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** are undefined.
726171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
726271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** A single database handle may have at most a single write-ahead log callback
726371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
726471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** previously registered write-ahead log callback. ^Note that the
726571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [sqlite3_wal_autocheckpoint()] interface and the
726671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
726771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** those overwrite any prior [sqlite3_wal_hook()] settings.
726871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
72693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API void *SQLITE_STDCALL sqlite3_wal_hook(
727071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  sqlite3*,
727171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  int(*)(void *,sqlite3*,const char*,int),
727271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori  void*
727371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori);
727471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
727571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
727671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Configure an auto-checkpoint
727771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
727871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
727971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** [sqlite3_wal_hook()] that causes any database on [database connection] D
728071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** to automatically [checkpoint]
728171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** after committing a transaction if there are N or
728271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** more frames in the [write-ahead log] file.  ^Passing zero or
728371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** a negative value as the nFrame parameter disables automatic
728471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** checkpoints entirely.
728571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
728671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The callback registered by this function replaces any existing callback
728771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
728871504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
728971504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** configured by this function.
72907790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project**
729171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
729271504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** from SQL.
729371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
72949bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** ^Checkpoints initiated by this mechanism are
72959bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** [sqlite3_wal_checkpoint_v2|PASSIVE].
72969bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown**
729771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** ^Every new [database connection] defaults to having the auto-checkpoint
729890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
729990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** pages.  The use of this interface
730071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** is only necessary if the default setting is found to be suboptimal
730171504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** for a particular application.
73027790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
73033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
730471504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
730571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori/*
730671504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori** CAPI3REF: Checkpoint a database
730771504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
73083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
73093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
731071504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori**
73113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
73123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [write-ahead log] for database X on [database connection] D to be
73133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** transferred into the database file and for the write-ahead log to
73143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** be reset.  See the [checkpointing] documentation for addition
73153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** information.
731690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
73173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This interface used to be the only way to cause a checkpoint to
73183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
73193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** interface was added.  This interface is retained for backwards
73203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** compatibility and as a convenience for applications that need to manually
73213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** start a callback but which do not need the full power (and corresponding
73223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** complication) of [sqlite3_wal_checkpoint_v2()].
732371504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori*/
73243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
732571504cf29d6d55df7d2aac17ecb160f7e5470553Vasu Nori
73267790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project/*
732790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Checkpoint a database
732890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
73293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
73303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** operation on database X of [database connection] D in mode M.  Status
73313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** information is written back into integers pointed to by L and C.)^
73323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^(The M parameter must be a valid [checkpoint mode]:)^
733390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
733490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dl>
733590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
73363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^Checkpoint as many frames as possible without waiting for any database
73373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   readers or writers to finish, then sync the database file if all frames
73383fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   in the log were checkpointed. ^The [busy-handler callback]
73393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
73403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^On the other hand, passive mode might leave the checkpoint unfinished
73413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   if there are concurrent readers or writers.
734290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
734390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_CHECKPOINT_FULL<dd>
73443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^This mode blocks (it invokes the
73459bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown**   [sqlite3_busy_handler|busy-handler callback]) until there is no
734690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**   database writer and all readers are reading from the most recent database
73473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   snapshot. ^It then checkpoints all frames in the log file and syncs the
73483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   database file. ^This mode blocks new database writers while it is pending,
73493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   but new database readers are allowed to continue unimpeded.
735090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
735190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_CHECKPOINT_RESTART<dd>
73523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
73533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   that after checkpointing the log file it blocks (calls the
73543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   [busy-handler callback])
73553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   until all readers are reading from the database file only. ^This ensures
73563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   that the next writer will restart the log file from the beginning.
73573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
73583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   database writer attempts while it is pending, but does not impede readers.
73593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
73603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
73613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
73623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   addition that it also truncates the log file to zero bytes just prior
73633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**   to a successful return.
736490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </dl>
736590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
73663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
73673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the log file or to -1 if the checkpoint could not run because
73683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
73693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
73703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** log file (including any that were already checkpointed before the function
73713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** was called) or to -1 if the checkpoint could not run due to an error or
73723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** because the database is not in WAL mode. ^Note that upon successful
73733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
73743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
73753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
73763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
737790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** any other process is running a checkpoint operation at the same time, the
73783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
737990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** busy-handler configured, it will not be invoked in this case.
738090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
73813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
73823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** exclusive "writer" lock on the database file. ^If the writer lock cannot be
73833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** obtained immediately, and a busy-handler is configured, it is invoked and
73843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the writer lock retried until either the busy-handler returns 0 or the lock
73853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** is successfully obtained. ^The busy-handler is also invoked while waiting for
73863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** database readers as described above. ^If the busy-handler returns 0 before
738790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** the writer lock is obtained or while waiting for database readers, the
738890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** checkpoint operation proceeds from that point in the same way as
738990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
73903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** without blocking any further. ^SQLITE_BUSY is returned in this case.
739190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
73923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If parameter zDb is NULL or points to a zero length string, then the
73933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** specified operation is attempted on all WAL databases [attached] to
73943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [database connection] db.  In this case the
73953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
739690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** an SQLITE_BUSY error is encountered when processing one or more of the
739790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** attached WAL databases, the operation is still attempted on any remaining
73983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** attached databases and SQLITE_BUSY is returned at the end. ^If any other
739990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** error occurs while processing an attached database, processing is abandoned
74003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** and the error code is returned to the caller immediately. ^If no error
740190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** (SQLITE_BUSY or otherwise) is encountered while processing the attached
740290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** databases, SQLITE_OK is returned.
740390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
74043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^If database zDb is the name of an attached database that is not in WAL
74053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
740690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** zDb is not NULL (or a zero length string) and is not the name of any
740790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** attached database, SQLITE_ERROR is returned to the caller.
74083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
74093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Unless it returns SQLITE_MISUSE,
74103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the sqlite3_wal_checkpoint_v2() interface
74113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** sets the error information that is queried by
74123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_errcode()] and [sqlite3_errmsg()].
74133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
74143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
74153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** from SQL.
741690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
74173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_wal_checkpoint_v2(
741890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  sqlite3 *db,                    /* Database handle */
741990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  const char *zDb,                /* Name of attached database (or NULL) */
742090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int eMode,                      /* SQLITE_CHECKPOINT_* value */
742190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int *pnLog,                     /* OUT: Size of WAL log in frames */
742290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown  int *pnCkpt                     /* OUT: Total number of frames checkpointed */
742390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown);
742490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
742590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
74263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** CAPI3REF: Checkpoint Mode Values
74273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** KEYWORDS: {checkpoint mode}
742890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
74293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** These constants define all valid values for the "checkpoint mode" passed
74303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
74313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
74323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** meaning of each of these checkpoint modes.
743390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
74343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
74353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
74363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for for readers */
74373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */
743890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
743990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
744090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Virtual Table Interface Configuration
744190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
744290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** This function may be called by either the [xConnect] or [xCreate] method
744390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of a [virtual table] implementation to configure
744490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** various facets of the virtual table interface.
744590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
744690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If this interface is invoked outside the context of an xConnect or
744790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** xCreate virtual table method then the behavior is undefined.
744890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
744990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** At present, there is only one option that may be configured using
745090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].)  Further options
745190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** may be added in the future.
745290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
74533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_CDECL sqlite3_vtab_config(sqlite3*, int op, ...);
745490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
745590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
745690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Virtual Table Configuration Options
745790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
745890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** These macros define the various options to the
745990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_vtab_config()] interface that [virtual table] implementations
746090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** can use to customize and optimize their behavior.
746190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
746290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dl>
746390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
746490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** <dd>Calls of the form
746590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
746690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** where X is an integer.  If X is zero, then the [virtual table] whose
746790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
746890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** support constraints.  In this configuration (which is the default) if
746990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
747090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
747190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** specified as part of the users SQL statement, regardless of the actual
747290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** ON CONFLICT mode specified.
747390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
747490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If X is non-zero, then the virtual table implementation guarantees
747590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
747690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** any modifications to internal or persistent data structures have been made.
747790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
747890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is able to roll back a statement or database transaction, and abandon
747990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** or continue processing the current SQL statement as appropriate.
748090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
748190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
748290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** had been ABORT.
748390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
748490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Virtual table implementations that are required to handle OR REPLACE
748590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** must do so within the [xUpdate] method. If a call to the
748690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [sqlite3_vtab_on_conflict()] function indicates that the current ON
748790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CONFLICT policy is REPLACE, the virtual table implementation should
748890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** silently replace the appropriate rows within the xUpdate callback and
748990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** return SQLITE_OK. Or, if this is not possible, it may return
749090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
749190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** constraint handling.
749290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** </dl>
749390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
749490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
749590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
749690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
749790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Determine The Virtual Table Conflict Policy
749890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
749990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** This function may only be called from within a call to the [xUpdate] method
750090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
750190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
750290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
750390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** of the SQL statement that triggered the call to the [xUpdate] method of the
750490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [virtual table].
750590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
75063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_vtab_on_conflict(sqlite3 *);
750790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
750890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
750990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** CAPI3REF: Conflict resolution modes
75109bee60b0fc0b60d4ae9e7533e0e6b7beca5f37fcJeff Brown** KEYWORDS: {conflict resolution mode}
751190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
751290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** These constants are returned by [sqlite3_vtab_on_conflict()] to
751390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** inform a [virtual table] implementation what the [ON CONFLICT] mode
751490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** is for the SQL statement being evaluated.
751590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown**
751690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** Note that the [SQLITE_IGNORE] constant is also used as a potential
751790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** return value from the [sqlite3_set_authorizer()] callback and that
751890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown** [SQLITE_ABORT] is also a [result code].
751990ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown*/
752090ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_ROLLBACK 1
752190ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
752290ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_FAIL     3
752390ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/* #define SQLITE_ABORT 4  // Also an error code */
752490ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown#define SQLITE_REPLACE  5
752590ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
75263fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich/*
75273fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** CAPI3REF: Prepared Statement Scan Status Opcodes
75283fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** KEYWORDS: {scanstatus options}
75293fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75303fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The following constants can be used for the T parameter to the
75313fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
75323fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** different metric for sqlite3_stmt_scanstatus() to return.
75333fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75343fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** When the value returned to V is a string, space to hold that string is
75353fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** managed by the prepared statement S and will be automatically freed when
75363fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** S is finalized.
75373fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75383fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dl>
75393fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
75403fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be
75413fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** set to the total number of times that the X-th loop has run.</dd>
75423fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75433fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
75443fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set
75453fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to the total number of rows examined by all iterations of the X-th loop.</dd>
75463fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75473fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
75483fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The "double" variable pointed to by the T parameter will be set to the
75493fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** query planner's estimate for the average number of rows output from each
75503fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** iteration of the X-th loop.  If the query planner's estimates was accurate,
75513fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** then this value will approximate the quotient NVISIT/NLOOP and the
75523fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** product of this value for all prior loops with the same SELECTID will
75533fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** be the NLOOP value for the current loop.
75543fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75553fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
75563fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The "const char *" variable pointed to by the T parameter will be set
75573fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to a zero-terminated UTF-8 string containing the name of the index or table
75583fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** used for the X-th loop.
75593fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75603fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
75613fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The "const char *" variable pointed to by the T parameter will be set
75623fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
75633fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** description for the X-th loop.
75643fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75653fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
75663fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** <dd>^The "int" variable pointed to by the T parameter will be set to the
75673fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** "select-id" for the X-th loop.  The select-id identifies which query or
75683fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** subquery the loop is part of.  The main query has a select-id of zero.
75693fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The select-id is the same value as is output in the first column
75703fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of an [EXPLAIN QUERY PLAN] query.
75713fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** </dl>
75723fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich*/
75733fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_NLOOP    0
75743fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_NVISIT   1
75753fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_EST      2
75763fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_NAME     3
75773fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_EXPLAIN  4
75783fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich#define SQLITE_SCANSTAT_SELECTID 5
75793fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich
75803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich/*
75813fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** CAPI3REF: Prepared Statement Scan Status
75823fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75833fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This interface returns information about the predicted and measured
75843fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** performance for pStmt.  Advanced applications can use this
75853fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** interface to compare the predicted and the measured performance and
75863fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
75873fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75883fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Since this interface is expected to be rarely used, it is only
75893fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
75903fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** compile-time option.
75913fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
75923fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The "iScanStatusOp" parameter determines which status information to return.
75933fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
75943fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** of this interface is undefined.
75953fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^The requested measurement is written into a variable pointed to by
75963fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the "pOut" parameter.
75973fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Parameter "idx" identifies the specific loop to retrieve statistics for.
75983fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** Loops are numbered starting from zero. ^If idx is out of range - less than
75993fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** zero or greater than or equal to the total number of loops used to implement
76003fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** the statement - a non-zero value is returned and the variable that pOut
76013fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** points to is unchanged.
76023fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
76033fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Statistics might not be available for all loops in all statements. ^In cases
76043fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** where there exist loops with no available statistics, this function behaves
76053fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** as if the loop did not exist - it returns non-zero and leave the variable
76063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** that pOut points to unchanged.
76073fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
76083fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** See also: [sqlite3_stmt_scanstatus_reset()]
76093fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich*/
76103fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_EXPERIMENTAL int SQLITE_STDCALL sqlite3_stmt_scanstatus(
76113fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
76123fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  int idx,                  /* Index of loop to report on */
76133fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
76143fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich  void *pOut                /* Result written here */
76153fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich);
76163fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich
76173fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich/*
76183fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** CAPI3REF: Zero Scan-Status Counters
76193fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
76203fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
76213fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich**
76223fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** This API is only available if the library is built with pre-processor
76233fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
76243fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick Kralevich*/
76253fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API SQLITE_EXPERIMENTAL void SQLITE_STDCALL sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
762690ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
762790ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown
762890ed05d921d6ed7f12012d9786d53f57fafee51aJeff Brown/*
76297790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** Undo the hack that converts floating point types to integer for
76307790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project** builds on processors without floating point support.
76317790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project*/
76327790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef SQLITE_OMIT_FLOATING_POINT
76337790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project# undef double
76347790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
76357790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project
76367790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#ifdef __cplusplus
76377790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project}  /* End of the 'extern "C"' block */
76387790ef5367fe6731048c3e3a1c067f94b321cb4dThe Android Open Source Project#endif
76398fecf56c625b5691ee3381e107ccbe1ff42398b1Nick Kralevich#endif /* _SQLITE3_H_ */
7640a4356a0ea71404ae414a07eafd7b95b91cc88c8cVasu Nori
7641de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori/*
7642de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** 2010 August 30
7643de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
7644de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** The author disclaims copyright to this source code.  In place of
7645de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** a legal notice, here is a blessing:
7646de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
7647de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**    May you do good and not evil.
7648de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**    May you find forgiveness for yourself and forgive others.
7649de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**    May you share freely, never taking more than you give.
7650de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
7651de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*************************************************************************
7652de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*/
7653de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7654de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#ifndef _SQLITE3RTREE_H_
7655de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#define _SQLITE3RTREE_H_
7656de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7657de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7658de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#ifdef __cplusplus
7659de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Noriextern "C" {
7660de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#endif
7661de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7662de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Noritypedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
76631c7cea379348522163370244e8fbbff8a136b7faNick Kralevichtypedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
76641c7cea379348522163370244e8fbbff8a136b7faNick Kralevich
76651c7cea379348522163370244e8fbbff8a136b7faNick Kralevich/* The double-precision datatype used by RTree depends on the
76661c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** SQLITE_RTREE_INT_ONLY compile-time option.
76671c7cea379348522163370244e8fbbff8a136b7faNick Kralevich*/
76681c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#ifdef SQLITE_RTREE_INT_ONLY
76691c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  typedef sqlite3_int64 sqlite3_rtree_dbl;
76701c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#else
76711c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  typedef double sqlite3_rtree_dbl;
76721c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#endif
7673de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7674de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori/*
7675de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** Register a geometry callback named zGeom that can be used as part of an
7676de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** R-Tree geometry query as follows:
7677de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**
7678de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
7679de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*/
76803fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_rtree_geometry_callback(
7681de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  sqlite3 *db,
7682de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  const char *zGeom,
76831c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
7684de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pContext
7685de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori);
7686de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7687de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7688de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori/*
7689de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** A pointer to a structure of the following type is passed as the first
7690de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori** argument to callbacks registered using rtree_geometry_callback().
7691de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori*/
7692de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Noristruct sqlite3_rtree_geometry {
7693de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
7694de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  int nParam;                     /* Size of array aParam[] */
76951c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
7696de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void *pUser;                    /* Callback implementation user data */
7697de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
7698de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori};
7699de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
77001c7cea379348522163370244e8fbbff8a136b7faNick Kralevich/*
77011c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** Register a 2nd-generation geometry callback named zScore that can be
77021c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** used as part of an R-Tree geometry query as follows:
77031c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
77041c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
77051c7cea379348522163370244e8fbbff8a136b7faNick Kralevich*/
77063fcd43a0f1ef02756029e12af3cb9ba9faa13364Nick KralevichSQLITE_API int SQLITE_STDCALL sqlite3_rtree_query_callback(
77071c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3 *db,
77081c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  const char *zQueryFunc,
77091c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int (*xQueryFunc)(sqlite3_rtree_query_info*),
77101c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  void *pContext,
77111c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  void (*xDestructor)(void*)
77121c7cea379348522163370244e8fbbff8a136b7faNick Kralevich);
77131c7cea379348522163370244e8fbbff8a136b7faNick Kralevich
77141c7cea379348522163370244e8fbbff8a136b7faNick Kralevich
77151c7cea379348522163370244e8fbbff8a136b7faNick Kralevich/*
77161c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** A pointer to a structure of the following type is passed as the
77171c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** argument to scored geometry callback registered using
77181c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** sqlite3_rtree_query_callback().
77191c7cea379348522163370244e8fbbff8a136b7faNick Kralevich**
77201c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** Note that the first 5 fields of this structure are identical to
77211c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** sqlite3_rtree_geometry.  This structure is a subclass of
77221c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** sqlite3_rtree_geometry.
77231c7cea379348522163370244e8fbbff8a136b7faNick Kralevich*/
77241c7cea379348522163370244e8fbbff8a136b7faNick Kralevichstruct sqlite3_rtree_query_info {
77251c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  void *pContext;                   /* pContext from when function registered */
77261c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int nParam;                       /* Number of function parameters */
77271c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_rtree_dbl *aParam;        /* value of function parameters */
77281c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  void *pUser;                      /* callback can use this, if desired */
77291c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  void (*xDelUser)(void*);          /* function to free pUser */
77301c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
77311c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  unsigned int *anQueue;            /* Number of pending entries in the queue */
77321c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int nCoord;                       /* Number of coordinates */
77331c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int iLevel;                       /* Level of current node or entry */
77341c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int mxLevel;                      /* The largest iLevel value in the tree */
77351c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_int64 iRowid;             /* Rowid for current entry */
77361c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
77371c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int eParentWithin;                /* Visibility of parent node */
77381c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  int eWithin;                      /* OUT: Visiblity */
77391c7cea379348522163370244e8fbbff8a136b7faNick Kralevich  sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
77401c7cea379348522163370244e8fbbff8a136b7faNick Kralevich};
77411c7cea379348522163370244e8fbbff8a136b7faNick Kralevich
77421c7cea379348522163370244e8fbbff8a136b7faNick Kralevich/*
77431c7cea379348522163370244e8fbbff8a136b7faNick Kralevich** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
77441c7cea379348522163370244e8fbbff8a136b7faNick Kralevich*/
77451c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define NOT_WITHIN       0   /* Object completely outside of query region */
77461c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define PARTLY_WITHIN    1   /* Object partially overlaps query region */
77471c7cea379348522163370244e8fbbff8a136b7faNick Kralevich#define FULLY_WITHIN     2   /* Object fully contained within query region */
77481c7cea379348522163370244e8fbbff8a136b7faNick Kralevich
7749de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7750de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#ifdef __cplusplus
7751de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori}  /* end of the 'extern "C"' block */
7752de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#endif
7753de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7754de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori#endif  /* ifndef _SQLITE3RTREE_H_ */
7755de2b3240539802d409a25760d5cec9d4ebfd6686Vasu Nori
7756